unstack, sort: cleanup and improvement

unstack, sort: cleanup and improvement

lets unstack
(a) know about in-kernel ipc entry points and
(b) be able handle >2GB symbol offsets.

	. sort: add -x for hex numerical sort
	. unstack: gnm is obsolete
	. unstack: datasizes is obsolete (use nm --size-sort instead)
	. unstack: add ipc entry points read from procfs (hex)
	. unstack: use sort -x to sort symbol order so the procfs ones are
	  sorted independent of position and original ordering