Migrate this to use clang by default as well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139936 91177308-0d34-0410-b5e6-96231b3b80d8

utils/buildit/build_llvm

@@ -97,13 +97,10 @@ if [ "$ARM_HOSTED_BUILD" = yes ]; then
     echo 'exec '$T' "$@"' >> $P || exit 1
     chmod a+x $P || exit 1
   done
-  # Try to use the platform llvm-gcc. Fall back to gcc if it's not available.
-  for prog in gcc g++ ; do
+  # Set up the links for clang.
+  for prog in clang clang++ ; do
     P=$DIR/bin/arm-apple-darwin$DARWIN_VERS-${prog}
-    T=`xcrun -sdk $SDKROOT -find llvm-${prog}`
-    if [ "x$T" = "x" ] ; then
-      T=`xcrun -sdk $SDKROOT -find ${prog}`
-    fi
+    T=`xcrun -sdk $SDKROOT -find ${prog}`
     echo '#!/bin/sh' > $P || exit 1
     echo 'exec '$T' -arch armv7 -isysroot '${SDKROOT}' "$@"' >> $P || exit 1
     chmod a+x $P || exit 1