drm/amdgpu: Fix '*fw' from request_firmware() not released in 'amdgpu_ucode_request()'

drm/amdgpu: Fix '*fw' from request_firmware() not released in 'amdgpu_ucode_request()'

Fixes the below:
drivers/gpu/drm/amd/amdgpu/amdgpu_ucode.c:1404 amdgpu_ucode_request() warn: '*fw' from request_firmware() not released on lines: 1404.

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Lijo Lazar <lijo.lazar@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>