wireguard: allowedips: avoid unaligned 64-bit memory accesses

In the Linux kernel, the following vulnerability has been resolved: wireguard: allowedips: avoid unaligned 64-bit memory accesses On the parisc platform, the kernel issues kernel warnings because swap_endian() tries to load a 128-bit IPv6 address from an unaligned memory location: Kernel: unaligned access to 0x55f4688c in wg_allowedips_insert_v6+0x2c/0x80 [wireguard] (iir 0xf3010df) Kernel: unaligned access to 0x55f46884 in wg_allowedips_insert_v6+0x38/0x80 [wireguard] (iir 0xf2010dc) Avoid such unaligned memory accesses by instead using the get_unaligned_be64() helper macro. [Jason: replace src[8] in original patch with src+8]