Revert "Disable clang optimization to boot up on arm64."

This reverts commit 1675f2c5581c7b0b83c8823e2b4eb0ec62b28b7f.

With latest Android source, now we can boot up without this workaround.

BUG: 19180814

Change-Id: I8a7852573856dbbe10a5f4823f7261b8ecc7490c
1 file changed