pvr: Don't allocate/upload 0 size coeff programs
Fixes assert seen in dEQP-Vk.api.smoke.triangle
Signed-off-by: Jarred Davies jarred.davies@imgtec.com
Fixes assert seen in dEQP-Vk.api.smoke.triangle
Signed-off-by: Jarred Davies jarred.davies@imgtec.com