m68k: vmlinux-std/sun3.lds.S cleanup - use PAGE_SIZE macro

This patch includes page.h header into linker script that
allow us to use PAGE_SIZE macro instead of numeric constant

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>