Add HISTORY sections to disk(9), driver(9), and

epoch(9).

In one instance, remove a trailing whitespace while here.

Submitted by:	gbergling_gmail.com
Approved by:	bcr
Differential Revision:	https://reviews.freebsd.org/D24243

share/man/man9/disk.9

@@ -27,7 +27,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd August 3, 2017
+.Dd April 30, 2020
 .Dt DISK 9
 .Os
 .Sh NAME
@@ -241,6 +241,11 @@ Typically used to store a pointer to the drivers
 .Vt softc
 structure for this disk device.
 .El
+.Sh HISTORY
+The
+.Nm kernel disk storage API
+first appeard in
+.Fx 4.9 .
 .Sh SEE ALSO
 .Xr GEOM 4 ,
 .Xr devfs 5 ,

share/man/man9/driver.9

@@ -28,7 +28,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd November 22, 2011
+.Dd April 30, 2020
 .Dt DRIVER 9
 .Os
 .Sh NAME
@@ -102,6 +102,11 @@ macro will also create the devclass with the name of the driver and
 can optionally call extra initialisation code in the driver by
 specifying an extra module event handler and argument as the last two
 arguments.
+.Sh HISTORY
+The
+.Nm
+framework first appeared in
+.Fx 2.2.7 .
 .Sh SEE ALSO
 .Xr devclass 9 ,
 .Xr device 9 ,

share/man/man9/epoch.9

@@ -26,7 +26,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd January 16, 2020
+.Dd April 30, 2020
 .Dt EPOCH 9
 .Os
 .Sh NAME
@@ -281,6 +281,11 @@ The
 .Nm
 kernel programming interface is under development and is subject to change.
 .El
+.Sh HISTORY
+The
+.Nm
+framework first appeard in
+.Fx 11.0 .
 .Sh SEE ALSO
 .Xr locking 9 ,
 .Xr mtx_pool 9 ,