[PATCH] mips: update IRQ handling for vr41xx

This patch has updated IRQ handling for vr41xx.
o added common IRQ dispatch
o changed IRQ number in int-handler.S
o added resource management to icu.c

Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>