i965: Pass brw_context to functions rather than intel_context.

i965: Pass brw_context to functions rather than intel_context.

This makes brw_context available in every function that used
intel_context.  This makes it possible to start migrating fields from
intel_context to brw_context.

Surprisingly, this actually removes some code, as functions that use
OUT_BATCH don't need to declare "intel"; they just use "brw."

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Acked-by: Chris Forbes <chrisf@ijw.co.nz>
Acked-by: Paul Berry <stereotype441@gmail.com>
Acked-by: Anuj Phogat <anuj.phogat@gmail.com>