drm/dp: Staticize a couple of DP utility functions
drm/dp: Staticize a couple of DP utility functions

sparse complains about these functions missing a prototype, but looking
closer they aren't (and likely not supposed to be) used outside of this
source file, so they can be made static.

Signed-off-by: Thierry Reding <3055038c414aef68bf32c33b8118623e7554e0f2@nvidia.com>
Reviewed-by: Alex Deucher <08dc22c6156113f2deff178e35e3ed9b24d6af9e@amd.com>
Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

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