drm/amd/display: remove incorrect early return

[Why&How]
Remove incorrect early return in a device specific fifo reset workaround

Reviewed-by: Leo Li <sunpeng.li@amd.com>
Reviewed-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>