drm/nouveau: fix off by one in BIOS boundary checking

In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: fix off by one in BIOS boundary checking Bounds checking when parsing init scripts embedded in the BIOS reject access to the last byte. This causes driver initialization to fail on Apple eMac's with GeForce 2 MX GPUs, leaving the system with no working console. This is probably only seen on OpenFirmware machines like PowerPC Macs because the BIOS image provided by OF is only the used parts of the ROM, not a power-of-two blocks read from PCI directly so PCs always have empty bytes at the end that are never accessed.