This must be the oldest bug that we have got.  Leaving interrupts "as
they are" for the R3000 obviously means copying IEp to IEc.  Since we have
got STATMASK now, I took this opportunity to mask the status register
"correctly" for the R3000 now too.  Oh, and the R3000 hardly ever is
64-bit.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>