rc.8: Add rc.suspend as an alias

Make it consistent with the other lifecycle scripts, thus making it
more findable.

Reviewed by:	ziaee
Signed-off-by:	Pat Maddox <pat@patmaddox.com>
Closes:		https://github.com/freebsd/freebsd-src/pull/2047

share/man/man8/Makefile

@@ -25,7 +25,8 @@ RCLINKS=	rc.8 rc.d.8 \
 		rc.8 rc.pccard.8 \
 		rc.8 rc.resume.8 \
 		rc.8 rc.serial.8 \
-		rc.8 rc.shutdown.8
+		rc.8 rc.shutdown.8 \
+		rc.8 rc.suspend.8
 RCPACKAGE=	rc
 
 .if ${MK_NIS} != "no"

share/man/man8/rc.8

@@ -44,6 +44,7 @@
 .Nm rc.resume
 .Nm rc.shutdown
 .Nm rc.subr
+.Nm rc.suspend
 .Sh DESCRIPTION
 The
 .Nm