Add initial sdma support for aldebaran, and this asic has 5 sdma instances.

v2: remove adundant condition check
Signed-off-by: NLe Ma <le.ma@amd.com>
Reviewed-by: NHawking Zhang <Hawking.Zhang@amd.com>
Acked-by: NEvan Quan <Evan.Quan@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>