intel/blorp: Always use UINT formats on SKL+

intel/blorp: Always use UINT formats on SKL+

Many of these UINT formats aren't available prior to Sky Lake so we used
UNORM formats.  Using UINT formats is a bit nicer because it guarantees we
don't run into rounding issues.  Also, we will need it in the next commit
for handling copies with CCS enabled.

Reviewed-by: Topi Pohjolainen <topi.pohjolainen@intel.com>