pkg: remove the release override, stable/xx.x will become release again

(cherry picked from commit 9821d6fb)

Makefile

@@ -47,11 +47,6 @@ CORE_BIND?=	911
 CORE_PHP?=	70
 CORE_PY?=	27
 
-.if "${CORE_RELEASE}" == yes
-CORE_NAME?=		opnsense
-CORE_FAMILY?=		release
-.endif
-
 _FLAVOUR!=	if [ -f ${OPENSSL} ]; then ${OPENSSL} version; fi
 FLAVOUR?=	${_FLAVOUR:[1]}
 
@@ -65,8 +60,8 @@ CORE_REPOSITORY?=	${FLAVOUR}
 
 CORE_PACKAGESITE?=	http://pkg.opnsense.org
 
-CORE_NAME?=		opnsense-stable
-CORE_FAMILY?=		stable
+CORE_NAME?=		opnsense
+CORE_FAMILY?=		release
 CORE_ORIGIN?=		opnsense/${CORE_NAME}
 CORE_COMMENT?=		OPNsense ${CORE_FAMILY} package
 CORE_MAINTAINER?=	franco@opnsense.org