Patched fbcon to compile on newer Linux kernels that don't #define PAGE_SIZE, since a memory page's size may vary on various architectures and kernel configurations. Will use getpagesize() if it exists, the PAGE_SIZE #define from older kernels if that doesn't, and #error out if that's not there either...but it's probably 4096 in that case. We may revisit this. Fixes Bugzilla #392.