drm/amd/display: don't call dc_interrupt_set() for disabled crtcs

As made mention of in commit 4ea7fc09 ("drm/amd/display: Do not
program interrupt status on disabled crtc"), we shouldn't program
disabled crtcs. So, filter out disabled crtcs in dm_set_vupdate_irq()
and dm_set_vblank().

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Fixes: 589d2739 ("drm/amd/display: Use crtc enable/disable_vblank hooks")
Fixes: d2574c33 ("drm/amd/display: In VRR mode, do DRM core vblank handling at end of vblank. (v2)")
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>