drm/amdgpu: fixing rlc firmware loading failure issue

Skip rlc firmware validation to ignore firmware header size mismatch issues.
This restores the workaround added in
commit 849e133c ("drm/amdgpu: Fix the null pointer when load rlc firmware")

Fixes: 3af2c80a ("drm/amdgpu: refine gfx10 firmware loading")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3551


Signed-off-by: Yang Wang <kevinyang.wang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 89ec85d1)