Use --enable-werror

Use --enable-werror during configure time rather than
--with-extra-options.  This is cleaner and easier to read.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172581 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/llvm-compilers-check b/utils/llvm-compilers-check
index 623ebc6..6a60d8a 100755
--- a/utils/llvm-compilers-check
+++ b/utils/llvm-compilers-check
@@ -353,16 +353,16 @@
 
         configure_flags = dict(
             llvm=dict(debug=["--prefix=" + self.install_prefix,
-                             "--with-extra-options=-Werror",
+                             "--enable-werror",
                              "--enable-assertions",
                              "--disable-optimized",
                              "--with-gcc-toolchain=" + cxxroot],
                       release=["--prefix=" + self.install_prefix,
-                               "--with-extra-options=-Werror",
+                               "--enable-werror",
                                "--enable-optimized",
                                "--with-gcc-toolchain=" + cxxroot],
                       paranoid=["--prefix=" + self.install_prefix,
-                                "--with-extra-options=-Werror",
+                                "--enable-werror",
                                 "--enable-assertions",
                                 "--enable-expensive-checks",
                                 "--disable-optimized",