Support CONFIG_GLOBAL_MOTION in the CMake build.
Support CONFIG_GLOBAL_MOTION in the CMake build.

BUG=https://bugs.chromium.org/p/aomedia/issues/detail?id=76

Change-Id: Ia56bdc8da422e9de9b92f357c98ad38017e8b728

GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom