target/mips: realign comments to fix checkpatch warnings

Realign comments to fix warnings issued by checkpatc.pl tool
 "WARNING: Block comments use a leading /* on a separate line"
within "target/mips/cpu.h" file.

Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Message-Id: <20190413202818.13622-3-jbi.octave@gmail.com>