i965: Use helper function intel_get_tile_dims() in surface setup
i965: Use helper function intel_get_tile_dims() in surface setup

It takes care of using the correct tile width if we later use other
tiling patterns for aux miptree.

V2: Remove the comment about using Yf for aux miptree.

Signed-off-by: Anuj Phogat <e2026475996c48f0b97fd37e84129b3912980428@gmail.com>
Reviewed-by: Chad Versace <a557f7f75bf28dc19ac99107f5cc7cd6b3fbdb1a@intel.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler