MIPS: Fix inconsistent formatting inside /proc/cpuinfo

There is a missing " " inside /proc/cpuinfo.

The bad commit was:
commit a96102be700f87283f168942cd09a2b30f86f324
Author: Steven J. Hill <sjhill@mips.com>
Date:   Fri Dec 7 04:31:36 2012 +0000
MIPS: Add printing of ISA version in cpuinfo.

Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/4988/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>