Don't try to compile ARM assembly when we're not compiling for ARM.

Change-Id: Ie32df975278f3e35eeacd02a43f16622c026a897
Revert "TEMPORARY: Disable qc-perf"

This reverts commit ba7b7c43919edd92b601b56ec13124f09601ecd8.
skia: Rename perf flag

Change-Id: If9f0976d9ba2ec22c4d9f70f203e033662ed0580