Revert "Revert "GPU: add optimization flags to GPU drivers""

This reverts commit de709bf80e82577ae313d26573df66584412009c.
Revert "block: account iowait time when waiting for completion of IO request"

This reverts commit a194e64a4b606b833e4604a6d06c41d520221bb1.
tweak CFLAGS
staging: android: LMK: Skip killing core apps

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>

Conflicts:
	drivers/staging/android/lowmemorykiller.c