Use gk20a_gmmu_{alloc,free}() instead of duplicating their code for page
tables. The linsim-specific special case is kept as-is.
JIRA DNVGPU-23
JIRA DNVGPU-20
Change-Id: I66d772337bad5d081256b13877c4e713ea8b634a
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: http://git-master/r/1139695
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>