ne: Do not use slashes in irq name string

This patch fixes following warning introduced by commit
12bac0d9

 ("proc: warn on non-existing
proc entries"):

WARNING: at /work/mips-linux/make/linux/fs/proc/generic.c:316 __xlate_proc_name+0xe0/0xe8()
name 'RBHMA4X00/RTL8019'

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>