drm/amd/display: Rebuild test pattern params for DP_TEST_PATTERN_VIDEO_MODE

[Why]
For video mode test pattern (i.e. test pattern disable), the call to
rebuild test pattern params for the pipe is skipped. This causes
dynamic disablement of test pattern to not work, as the
test_pattern_params of the pipe will not be updated and retain the
values of the previously enabled test pattern.

[How]
Rebuild test pattern params even when test pattern is video mode,
allowing the pipe to have updated test_pattern_params values.

Reviewed-by: Nevenko Stupar <nevenko.stupar@amd.com>
Reviewed-by: Chaitanya Dhere <chaitanya.dhere@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>