i965: Add _CACHE_ in brw_cache_id enum names.

i965: Add _CACHE_ in brw_cache_id enum names.

BRW_CACHE_VS_PROG is more easily associated with program caches than
plain BRW_VS_PROG.

While we're at it, rename BRW_WM_PROG to BRW_CACHE_FS_PROG, to move away
from the outdated Windowizer/Masker name.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
Reviewed-by: Matt Turner <mattst88@gmail.com>