skia_bench: build with optimizations when available

skia_bench currently doesn't built with certain CFLAGS that
could optimize it. These were pulled in from the main skia
make file.

Change-Id: I0f466f6ca46a9e3ff448ce6047a68905f789462e
Signed-off-by: Andy Doan <andy.doan@linaro.org>
1 file changed