drm/nv4c/bios: disallow retrieving from prom on nv4x igp's
drm/nv4c/bios: disallow retrieving from prom on nv4x igp's

Suggested-by: Marcin Kościelnicki <745187515eb483e9471d9177f0aa2ef6797ac3c9@0x04.net>
Signed-off-by: Ilia Mirkin <bcbbb7aa705ec3a5fc5824c01a845186c3d62fca@alum.mit.edu>
Signed-off-by: Ben Skeggs <d9f27fb07c1e9f131223ad827fa5179f3846c30b@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs