drm/amdgpu: replace ih ip block for vega20 and arcturus

[Why]
Vega20 and Arcturus asics use oss 5.0 version.

[How]
Replace ih ip block by navi10 for vega20 and arcturus.

Signed-off-by: Alex Sierra <alex.sierra@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>