UPDATING: Add an updating entry for MIT KRB5 MIT KRB5 is not default.

People may wish to play with it before it does become default. Add an
UPDATING entry to discuss the anything required to update.

Bump __FreeBSD_version to indicate that MIT KRB5 has been imported.

We will see an another __FreeBSD_version bump when MIT KRB5 becomes
the default Kerberos.

UPDATING

@@ -27,6 +27,23 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 15.x IS SLOW:
 	world, or to merely disable the most expensive debugging functionality
 	at runtime, run "ln -s 'abort:false,junk:false' /etc/malloc.conf".)
 
+20250614:
+	MIT KRB5 (MIT Kerberos5) has been imported into 15-CURRENT. To
+	and install MIT KRB5, add WITH_MITKRB5=yes to /etc/src.conf. This
+	will build and install MIT KRB5 1.21.3. And it will remove Heimdal
+	1.5.2 when delete-old and delete-old-libs are run. To revert back
+	simply buildworld/installworld again with delete-old-libs and
+	delete-old.
+
+	At the moment we only know of a couple of ports that might be
+	affected. Adjusting libmap.conf does not circumvent runtime issues.
+	The few affected ports must be rebuilt. A successful exp-run will be
+	run before MIT KRB5 becomes default.
+
+	Those using the KDC in FreeBSD base may wish to wait. The Heimdal
+	HDB is incompatible with the MIT KRB5 KDC. The migration procedure
+	is a little involved.
+
 20250603:
 	LinuxKPI dma-mapping.h were pulled into the tree from drm-kmod.
 	Bump _FreeBSD_version to 1500045 to be able to detect this change.

sys/sys/param.h

@@ -73,7 +73,7 @@
  * cannot include sys/param.h and should only be updated here.
  */
 #undef __FreeBSD_version
-#define __FreeBSD_version 1500046
+#define __FreeBSD_version 1500047
 
 /*
  * __FreeBSD_kernel__ indicates that this system uses the kernel of FreeBSD,