drm/amd/display: Revert FEC check in validation

stable inclusion
from stable-v5.10.112
commit 34ea097fb63d116d857e6c23b97cb94ff02ccf42
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5HL0X

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=34ea097fb63d116d857e6c23b97cb94ff02ccf42

--------------------------------

[ Upstream commit b2075fce ]

why and how:
causes failure on install on certain machines
Reviewed-by: NGeorge Shen <George.Shen@amd.com>
Acked-by: NAlex Hung <alex.hung@amd.com>
Signed-off-by: NMartin Leung <Martin.Leung@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -1173,10 +1173,6 @@ bool dc_validate_seamless_boot_timing(const struct dc *dc,
 	if (!link->link_enc->funcs->is_dig_enabled(link->link_enc))
 		return false;
 
-	/* Check for FEC status*/
-	if (link->link_enc->funcs->fec_is_active(link->link_enc))
-		return false;
-
 	enc_inst = link->link_enc->funcs->get_dig_frontend(link->link_enc);
 
 	if (enc_inst == ENGINE_ID_UNKNOWN)