cmake, doc: Update depends/README.md

Author: hebasto

depends/README.md

@@ -12,17 +12,13 @@ For example:
 
     make HOST=x86_64-w64-mingw32 -j4
 
-**Bitcoin Core's `configure` script by default will ignore the depends output.** In
+**When configuring Bitcoin Core, CMake by default will ignore the depends output.** In
 order for it to pick up libraries, tools, and settings from the depends build,
-you must set the `CONFIG_SITE` environment variable to point to a `config.site` settings file.
-Make sure that `CONFIG_SITE` is an absolute path.
-In the above example, a file named `depends/x86_64-w64-mingw32/share/config.site` will be
-created. To use it during compilation:
+you must specify the toolchain file.
+In the above example, a file named `depends/x86_64-w64-mingw32/toolchain.cmake` will be
+created. To use it during configuring Bitcoin Core:
 
-    CONFIG_SITE=$PWD/depends/x86_64-w64-mingw32/share/config.site ./configure
-
-The default install prefix when using `config.site` is `--prefix=depends/<host-platform-triplet>`,
-so depends build outputs will be installed in that location.
+    cmake -B build --toolchain depends/x86_64-w64-mingw32/toolchain.cmake
 
 Common `host-platform-triplet`s for cross compilation are:
 

depends/funcs.mk

@@ -171,7 +171,7 @@ $(1)_autoconf += LDFLAGS="$$($(1)_ldflags)"
 endif
 
 # We hardcode the library install path to "lib" to match the PKG_CONFIG_PATH
-# setting in depends/config.site.in, which also hardcodes "lib".
+# setting in depends/toolchain.cmake.in, which also hardcodes "lib".
 # Without this setting, CMake by default would use the OS library
 # directory, which might be "lib64" or something else, not "lib", on multiarch systems.
 $(1)_cmake=env CC="$$($(1)_cc)" \