pkgbase: Move tr(1) to runtime

Since f7d16a6 ("certctl: Convert line endings before inspecting files.")
certctl is using tr(1). Add it to FreeBSD-runtime so we can have certctl working
without having the bloated FreeBSD-utilities.

Sponsored by:	Beckhoff Automation GmbH & Co. KG

usr.bin/tr/Makefile

@@ -1,6 +1,7 @@
 
 .include <src.opts.mk>
 
+PACKAGE=	runtime
 PROG=	tr
 SRCS=	cmap.c cset.c str.c tr.c