i965/gen8: Don't enable alpha test and alpha to coverage if draw bufer zero is integer type
i965/gen8: Don't enable alpha test and alpha to coverage if draw bufer zero is integer type

We follow this rule at multiple places in i965 driver. This patch
doesn't fix any testcase.

Signed-off-by: Anuj Phogat <e2026475996c48f0b97fd37e84129b3912980428@gmail.com>
Reviewed-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler