drm/amdkfd: get doorbell's absolute offset based on the db_size

Here, Adding db_size in byte to find the doorbell's
absolute offset for both 32-bit and 64-bit doorbell sizes.
So that doorbell offset will be aligned based on the doorbell
size.

v2:
- Addressed the review comment from Felix.
v3:
- Adding doorbell_size as parameter to get db absolute offset.
v4:
  Squash the two patches into one.

Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Shashank Sharma <shashank.sharma@amd.com>
Signed-off-by: Arvind Yadav <Arvind.Yadav@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c

@@ -377,7 +377,8 @@ int pqm_create_queue(struct process_queue_manager *pqm,
 		 */
 		uint32_t first_db_index = amdgpu_doorbell_index_on_bar(pdd->dev->adev,
 								       pdd->qpd.proc_doorbells,
-								       0);
+								       0,
+								       pdd->dev->kfd->device_info.doorbell_size);
 
 		*p_doorbell_offset_in_process = (q->properties.doorbell_off
 						- first_db_index) * sizeof(uint32_t);