drm/amdgpu: Add new members for sdma v7_0 fw

Add new members in sdma instance structure
for sdma v7_0 firmware.

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