MAINTAINERS/CODEOWNERS: Add myself to mpr, mps and mpi3mr

Yea, I realize these are decaying, but I'm going to take a run at
automatically tagging reviews for github pull requests. I suspect that
tagging will help with the 'stale' issues with at least CODEOWNER.  As
better data becomes available, especailly for contrib, I'll update
things.

Sponsored by:		Netflix

.github/CODEOWNERS

@@ -83,6 +83,9 @@
 /sys/dev/iscsi/	@trasz
 /sys/dev/nctgpio/	@stephane-rochoy-stormshield
 /sys/dev/ncthwm/	@stephane-rochoy-stormshield
+/sys/dev/mpi3mr	@bsdimp
+/sys/dev/mps	@bsdimp
+/sys/dev/mpr	@bsdimp
 /sys/dev/nvd	@bsdimp
 /sys/dev/nvme	@bsdimp
 /sys/dev/pci	@bsdimp @bsdjhb