drm/amd/display: Fix bug preventing FCLK Pstate allow message being sent

[Why & How]
FCLK pstate allow message should not be dependent on local
"update_fclk".

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Martin Leung <Martin.Leung@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Dillon Varone <Dillon.Varone@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>