Compression page size varies depending on architecture. Make it
129kB on gk20a and gm20b.
Also export some common functions from gm20b.
Bug 1592495
Change-Id: Ifb1c5b15d25fa961dab097021080055fc385fecd
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/673790