drm/amd/display: Simplify if conditions

drm/amd/display: Simplify if conditions

The if conditions !A || A && B can be simplified to !A || B.

Fixes the following Coccinelle/coccicheck warnings reported by
excluded_middle.cocci:

	WARNING !A || A && B is equivalent to !A || B
	WARNING !A || A && B is equivalent to !A || B
	WARNING !A || A && B is equivalent to !A || B

Compile-tested only.

Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>