Revert GCC_INSTALL_PREFIX bypass

Author: hamphet

clang/CMakeLists.txt

@@ -203,7 +203,7 @@ set(CLANG_RESOURCE_DIR "" CACHE STRING
 set(C_INCLUDE_DIRS "" CACHE STRING
   "Colon separated list of directories clang will search for headers.")
 
-set(USE_DEPRECATED_GCC_INSTALL_PREFIX ON CACHE BOOL "Temporary workaround before GCC_INSTALL_PREFIX is completely removed")
+set(USE_DEPRECATED_GCC_INSTALL_PREFIX OFF CACHE BOOL "Temporary workaround before GCC_INSTALL_PREFIX is completely removed")
 set(GCC_INSTALL_PREFIX "" CACHE PATH "Directory where gcc is installed." )
 set(DEFAULT_SYSROOT "" CACHE STRING
   "Default <path> to all compiler invocations for --sysroot=<path>." )