MFC r318790, r319336

r318790:
Fix a buffer overflow in bootparamd(8)

If /etc/bootparams contains a line with an excessively long pathname, and a
client asks for that path, then bootparamd will overflow a buffer and crash
while parsing that line. This is not remotely exploitable since it requires
a malformed /etc/bootparams file.

Reported by: Coverity
CID: 1305954
Sponsored by: Spectra Logic Corp

r319336:
Fix uninitialized variable in bootparamd.c

Restore line that was accidentally deleted in change 318790

Reported by: Coverity
CID: 1375855
X-MFC-With: 318790
Sponsored by: Spectra Logic Corp