drm/amd/display: Fix multiple cursors when using 4 displays on a contiguous large surface

[Why & How]
Remove some cursor offset calculations for rotated cursor for fixing a bug where multiple cursors are seen.

Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Acked-by: Zaeem Mohamed <zaeem.mohamed@amd.com>
Signed-off-by: Nevenko Stupar <nevenko.stupar@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>