drm/amdkfd: Update context save handling for multi XCC setup (v2)

Context save handling needs to be updated for a multi XCC
setup:
- On a multi XCC setup, KFD needs to report context save base
  address and size for each XCC in MQD.
- Thunk will allocate a large context save area covering all
  XCCs which will be equal to: num_of_xccs in a partition * size
  of context save area for 1 XCC. However, it will report only the
  size of context save area for 1 XCC only in the ioctl call.
- Driver then setups the MQD correctly using the size passed from
  Thunk and information about number of XCCs in a partition.
- Update get_wave_state function to return context save area
  for all XCCs in the partition.

v2: update the get_wave_state function for mqd manager v11 (Morris)

Signed-off-by: Mukul Joshi <mukul.joshi@amd.com>
Tested-by: Amber Lin <Amber.Lin@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Morris Zhang <Shiwu.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>