Blorp doesn't handle spilling so we set allow_spilling to false in that
case. The blorp 16x MSAA resolve shader spills in 16-wide but not 8-wide.
This commit makes it so that we fail the 16-wide compile and successfully
fall back to 8-wide instead of just assert-failing when trying to compile
the 16-wide shader.
Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
175ac629be