drm/amdgpu: Add osssys v7_1_0 ip headers v3

Add header files for osssys v7_1_0 register offsets
and shift masks
v2: Update osssys v7_1_0 ip headers to the latest version
v3: Clean up registers (Alex)

Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Likun Gao <Likun.Gao@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>