parisc: fix LMMIO mismatch between PAT length and MASK register

The LMMIO length reported by PAT and the length given by the LBA MASK
register are not consistent. This leads e.g. to a not-working ATI FireGL
card with the radeon DRM driver since the memory can't be mapped.

Fix this by correctly adjusting the resource sizes.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # 3.10