drm/amdgpu: enhance amdgpu_ucode_request() function flexibility

v1:
Adding formatting string feature to improve function flexibility.

v2:
modify macro name to ADMGPU_UCODE_MAX_NAME.

Signed-off-by: Yang Wang <kevinyang.wang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>