drm/amdgpu: Fix up missing parameters kdoc in svm_migrate_vma_to_ram

Fix these warnings by adding & deleting the deviant arguments.

gcc with W=1
drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_migrate.c:671: warning: Function parameter or member 'node' not described in 'svm_migrate_vma_to_ram'
drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_migrate.c:671: warning: Function parameter or member 'trigger' not described in 'svm_migrate_vma_to_ram'
drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_migrate.c:671: warning: Function parameter or member 'fault_page' not described in 'svm_migrate_vma_to_ram'
drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_migrate.c:671: warning: Excess function parameter 'adev' description in 'svm_migrate_vma_to_ram'
drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_migrate.c:771: warning: Function parameter or member 'fault_page' not described in 'svm_migrate_vram_to_ram'

Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>