MIPS: Add printing of ES bit for Imgtec cores when cache error occurs.

The cacheer register is always implemented in the same way in the
MIPS32r2 Imgtec cores so print the ES bit when an cache error
occurs.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6041/