Four basic reasons as below to do the change:
  1. number of ring expand a lot on aqua_vanjaram, and adjustment on old
     assignment cannot make each ring in a continuous doorbell space.
  2. the SDMA doorbell index should not exceed 0x1FF on aqua_vanjaram due to
     regDOORBELLx_CTRL_ENTRY.BIF_DOORBELLx_RANGE_OFFSET_ENTRY field width.
  3. re-design the doorbell assignment and unify the calculation as
     "start + ring/inst id" will make the code much concise.
  4. only defining the START/END makes the table look simple

v2: (Lijo)
  1. replace name
  2. use num_inst_per_aid/sdma_doorbell_range instead of hardcoding
Signed-off-by: Le Ma <le.ma@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>