Undefined name: cflags --> ldflags

@rvagg This would be good to land before #1892

The current code would raise NameError at runtime.

Author: cclauss

gyp/pylib/gyp/xcode_emulation.py

@@ -846,7 +846,7 @@ def GetLdflags(self, configname, product_dir, gyp_to_build_path, arch=None):
     if self._IsXCTest():
       platform_root = self._XcodePlatformPath(configname)
       if platform_root:
-        cflags.append('-F' + platform_root + '/Developer/Library/Frameworks/')  # noqa TODO @cclauss
+        ldflags.append('-F' + platform_root + '/Developer/Library/Frameworks/')
 
     is_extension = self._IsIosAppExtension() or self._IsIosWatchKitExtension()
     if sdk_root and is_extension: