MFC r329845, r329872

r329845:
Fix numerous Coverity issues in mptutil

Most are memory or file descriptor leaks. Three were unannotated
fallthroughs in a switch/case statement. One was an integer overflow before
widen.

Reported by: Coverity
CID: 1007463 1007462 1007461 1007460 1007459 1007458 1007457
CID: 1006855 1006854 1006853 1006852 1006851 1006850 1006849
CID: 1006848 1006845 1006844 1006843 1006842 1006841 1006840
CID: 1006839 1006838 1006837 1006836 1006835 1006834 1006833
CID: 1006832 1006831 1006831 1006830 1006829 1008334 1008170
CID: 1008169 1008168
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D11013

r329872:
Delete copypasta

Reported by: rpokala
X-MFC-With: 329845
Sponsored by: Spectra Logic Corp