Move CURSES_LIBS workaround to Azure yaml

This allows _build-deps.yml to be Centos6-specific, while
`install-crosstool-ng.sh` can be called from other environments.

Author: jwnrt

_build-deps.yml

@@ -11,6 +11,15 @@ steps:
   displayName: 'Install build dependencies'
 
 - bash: |
+    # Explicitly include libtinfo in the ncurses linker options since it seems to be
+    # not picked up by configure itself, leading to the following error otherwise:
+    #
+    # /usr/local/bin/libtool  --tag CC  --mode=link gcc  -g -O2   -o nconf nconf-nconf.o nconf-nconf.gui.o nconf-zconf.o -lmenuw -lpanelw -lncursesw
+    # libtool: link: gcc -g -O2 -o nconf nconf-nconf.o nconf-nconf.gui.o nconf-zconf.o  -lmenuw -lpanelw -lncursesw
+    # /opt/rh/devtoolset-8/root/usr/libexec/gcc/x86_64-redhat-linux/8/ld: nconf-nconf.o: undefined reference to symbol 'keypad'
+    # //lib64/libtinfo.so.5: error adding symbols: DSO missing from command line
+    export CURSES_LIBS="-lcursesw -ltinfo"
+
     ./install-crosstool-ng.sh
   displayName: 'Build and install crosstool-ng'
 

install-crosstool-ng.sh

@@ -20,11 +20,4 @@ git checkout --force "${CROSSTOOL_NG_VERSION}"
 
 ./bootstrap
 
-# Explicitly include libtinfo in the ncurses linker options since it seems to be
-# not picked up by configure itself, leading to the following error otherwise:
-#
-# /usr/local/bin/libtool  --tag CC  --mode=link gcc  -g -O2   -o nconf nconf-nconf.o nconf-nconf.gui.o nconf-zconf.o -lmenuw -lpanelw -lncursesw
-# libtool: link: gcc -g -O2 -o nconf nconf-nconf.o nconf-nconf.gui.o nconf-zconf.o  -lmenuw -lpanelw -lncursesw
-# /opt/rh/devtoolset-8/root/usr/libexec/gcc/x86_64-redhat-linux/8/ld: nconf-nconf.o: undefined reference to symbol 'keypad'
-# //lib64/libtinfo.so.5: error adding symbols: DSO missing from command line
-CURSES_LIBS="-lcursesw -ltinfo" ./configure --prefix=/usr/local && make && sudo make install
+./configure --prefix=/usr/local && make && sudo make install