MIPS: Please revert "MIPS: Fix PAGE_MASK definition"

[Manuel Lauss <manuel.lauss@xxxxxxxxx>]

Hello,

Commit 22b14523994588279ae9c5ccfe64073c1e5b3c00 ("MIPS: Fix PAGE_MASK
definition")
breaks the extended 36bit IO space on Alchemy (i.e. PCI and PCMCIA don't work).
A simple revert fixes it. (Additionally, I've actually never seen the
warning it is supposed to fix
in my 32 bit builds).

Thanks!
     Manuel Lauss