tools: use CC instead of CXX when pointing to gcc

Current CC flag points to g++ instead of gcc which is causing failures
when compiling V8.

PR-URL: #30817
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

tools/make-v8.sh

@@ -15,12 +15,15 @@ if [[ "$ARCH" == "s390x" ]] || [[ "$ARCH" == "ppc64le" ]]; then
   if [[ X"$CXX" != X ]]; then
     CXX_PATH=`which $CXX |grep g++`
   fi
+  if [[ X"$CC" != X ]]; then
+    CC_PATH=`which $CC |grep gcc`
+  fi
   rm -f "$BUILD_TOOLS/g++"
   rm -f "$BUILD_TOOLS/gcc"
 fi
 if [[ "$ARCH" == "s390x" ]]; then
   ln -s $CXX_PATH "$BUILD_TOOLS/g++"
-  ln -s $CXX_PATH "$BUILD_TOOLS/gcc"
+  ln -s $CC_PATH "$BUILD_TOOLS/gcc"
   g++ --version
   export PKG_CONFIG_PATH=$BUILD_TOOLS/pkg-config
   gn gen -v out.gn/$BUILD_ARCH_TYPE --args='is_component_build=false is_debug=false use_goma=false goma_dir="None" use_custom_libcxx=false v8_target_cpu="s390x" target_cpu="s390x"'