drm: radeon: fix error value sign
drm: radeon: fix error value sign

enable_vblank implementations should use negative result to indicate error.
radeon_enable_vblank() returns EINVAL in this case.  Change this to -EINVAL.

Signed-off-by: Vasiliy Kulikov <942b402b07c522a8271785df04894b4692262f69@openwall.com>
Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas