MFC r317154,r317155,r317162,r317163,r317164:

r317154:

Print out the signal number on exit in terminate(..) if WARMSTART is compiled
into rpcbind.

The signal number can provide helpful diagnostic info.

Obtained from: Isilon OneFS

r317155:

rpcbind(8): wordsmith -h description and mention -W in the SYNOPSIS section

-W was already documented in the OPTIONS section.

r317162:

rpcbind(8): add a description for /var/run/rpcbind.sock under the FILES section

r317163:

rpcbind(8): post-humously document -w (warmstart) support added in r74462

warmstart support saves portmap/rpcbind(8) registration state on exit and
restores the saved registration state on restart.

r317164:

Fix indentation per style.Makefile(5)