drm/nouveau/nvif: fix dac load detect method definition
drm/nouveau/nvif: fix dac load detect method definition

A thinko made me turn this into a u16 when cleaning up.

Spotted by coverity.

Signed-off-by: Ben Skeggs <d9f27fb07c1e9f131223ad827fa5179f3846c30b@redhat.com>

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