Vidmem size query was in mm_xxx.c. It involves reading a register from FB, so move the query to FB HAL. JIRA NVGPU-1063 Change-Id: I30dfd2c4fdcdd6c841f85aaab7431d52473759bd Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com> Reviewed-on: https://git-master.nvidia.com/r/1801425 Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com> Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>