Merge bitcoin#23269: build: remove redundant warning flags

aa69fd6 build: Drop -Wno-unused-local-typedef (Hennadii Stepanov)
672e8c5 build: remove -Wunused-variable (fanquake)
5239af0 build: remove -Wswitch (fanquake)
0375906 build: use loop-analysis over range-loop-analysis (fanquake)
12712fa build: remove -Wsign-compare (fanquake)

Pull request description:

  This remove the addition of flags that are already part of other options, such as `-Wall` or `-Wextra`; see each commit message for details. All of the flags being removed here already exist as part of `-Wall` as of GCC 8, or, for Clang, all exist in `-Wmost` (included in `-Wall)`, or as part of `-Wextra` as of Clang 7. Both of which are our minimum required compilers.

  Also cherry-picks one change from bitcoin#21458.

  To give an example of how GCCs `-Wall` has changed over the last few releases:
  ### 11.x to trunk (12.x)
  Added:
  ```bash
  -Wzero-length-bounds
  -Wmismatched-dealloc
  -Wmismatched-new-delete (only for C/C++)
  ```

  ### 10.x to 11.x
  Added:
  ```bash
  -Warray-parameter=2 (C and Objective-C only)
  -Wrange-loop-construct (only for C++)
  -Wsizeof-array-div
  -Wvla-parameter (C and Objective-C only)
  ```

  Removed:
  ```bash
  -Wenum-conversion in C/ObjC;
  ```

  ### 9.x to 10.x
  Added:
  ```bash
  -Wenum-conversion in C/ObjC;
  -Wformat-overflow
  -Wformat-truncation
  -Wzero-length-bounds
  ```

  ### 8.x to 9.x
  Added:
  ```bash
  -Wpessimizing-move
  ```

  Removed:
  ```bash
  -Wstringop-truncation
  ```

  ### 7.x to 8.x
  Added:
  ```bash
  -Wcatch-value (C++ and Objective-C++ only)
  -Wmissing-attributes
  -Wmultistatement-macros
  -Wrestrict
  -Wsizeof-pointer-div
  -Wstringop-truncation
  ```

  [Clang Warning Options](https://clang.llvm.org/docs/DiagnosticsReference.html)
  [GCC Warning Options](https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html)

ACKs for top commit:
  meshcollider:
    utACK aa69fd6

Tree-SHA512: 34dde6bd773c864202c151eaa35f902d03fb531c27fe5e1ef659225da03acade2efe5df56df3efb4df5bbded3d395348ce03c25b837fce83be53af3352f0f2bc

Author: fanquake

configure.ac

@@ -425,15 +425,12 @@ if test "x$CXXFLAGS_overridden" = "xno"; then
   AX_CHECK_COMPILE_FLAG([-Wformat -Wformat-security],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wformat -Wformat-security"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wvla],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wvla"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wshadow-field],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wshadow-field"],,[[$CXXFLAG_WERROR]])
-  AX_CHECK_COMPILE_FLAG([-Wswitch],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wswitch"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wthread-safety],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wthread-safety"],,[[$CXXFLAG_WERROR]])
-  AX_CHECK_COMPILE_FLAG([-Wrange-loop-analysis],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wrange-loop-analysis"],,[[$CXXFLAG_WERROR]])
+  AX_CHECK_COMPILE_FLAG([-Wloop-analysis],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wloop-analysis"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wredundant-decls],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wredundant-decls"],,[[$CXXFLAG_WERROR]])
-  AX_CHECK_COMPILE_FLAG([-Wunused-variable],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wunused-variable"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wunused-member-function],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wunused-member-function"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wdate-time],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wdate-time"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wconditional-uninitialized],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wconditional-uninitialized"],,[[$CXXFLAG_WERROR]])
-  AX_CHECK_COMPILE_FLAG([-Wsign-compare],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wsign-compare"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wduplicated-branches],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wduplicated-branches"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wduplicated-cond],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wduplicated-cond"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wlogical-op],[WARN_CXXFLAGS="$WARN_CXXFLAGS -Wlogical-op"],,[[$CXXFLAG_WERROR]])
@@ -454,7 +451,6 @@ if test "x$CXXFLAGS_overridden" = "xno"; then
   dnl set the -Wno-foo case if it works.
   AX_CHECK_COMPILE_FLAG([-Wunused-parameter],[NOWARN_CXXFLAGS="$NOWARN_CXXFLAGS -Wno-unused-parameter"],,[[$CXXFLAG_WERROR]])
   AX_CHECK_COMPILE_FLAG([-Wself-assign],[NOWARN_CXXFLAGS="$NOWARN_CXXFLAGS -Wno-self-assign"],,[[$CXXFLAG_WERROR]])
-  AX_CHECK_COMPILE_FLAG([-Wunused-local-typedef],[NOWARN_CXXFLAGS="$NOWARN_CXXFLAGS -Wno-unused-local-typedef"],,[[$CXXFLAG_WERROR]])
   if test x$suppress_external_warnings != xyes ; then
     AX_CHECK_COMPILE_FLAG([-Wdeprecated-copy],[NOWARN_CXXFLAGS="$NOWARN_CXXFLAGS -Wno-deprecated-copy"],,[[$CXXFLAG_WERROR]])
   fi