Update in preparation of 13.1-RELEASE

- Bump BRANCH to RELEASE
- Add the anticipated RELEASE announcement date
- Set a static __FreeBSD_version

Approved by:	re (implicit)
Sponsored by:	Rubicon Communications, LLC ("Netgate")

UPDATING

@@ -12,6 +12,9 @@ Items affecting the ports and packages system can be found in
 /usr/ports/UPDATING.  Please read that file before updating system packages
 and/or ports.
 
+20220516:
+	13.1-RELEASE.
+
 20220123:
 	For 64-bit architectures the base system is now built with Position
 	Independent Executable (PIE) support enabled by default.  It may be

lib/csu/common/crtbrand.S

@@ -45,5 +45,5 @@ __FBSDID("$FreeBSD$");
 	.4byte		NT_FREEBSD_ABI_TAG
 1:	.asciz		NOTE_FREEBSD_VENDOR
 2:	.p2align	2
-3:	.4byte		__FreeBSD_version
+3:	.4byte		1301000
 4:

sys/conf/newvers.sh

@@ -54,7 +54,7 @@
 
 TYPE="FreeBSD"
 REVISION="13.1"
-BRANCH="RC6"
+BRANCH="RELEASE"
 if [ -n "${BRANCH_OVERRIDE}" ]; then
 	BRANCH=${BRANCH_OVERRIDE}
 fi