drm/vmwgfx: Split GMR2_REMAP commands if they are to large

commit 6e4dcff3adbf25acb87e74500a58e3c07bdec40f upstream.

This fixes the piglit test texturing/max-texture-size
causing the VM to die due to a too large SVGA command.

Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Reviewed-by: Biran Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>