* sysdep.c (sys_suspend): Don't try to use "nice (- nice (0))" to

* sysdep.c (sys_suspend): Don't try to use "nice (- nice (0))" to
	set the subshell's priority to normal; nice doesn't return a
	defined value on all systems.  Instead, since emacs_priority gives
	the priority that Emacs was nastied to, we can use it to reset the
	priority in a straightforward way.
	[BSD4_1], [USG], [VMS] (setpriority): Remove dummy and
	compatibility definitions of setpriority.