find(1): Update date format reference and remove cvs(1) references

cvs(1) is not installed by default. Change the date format reference to
note that find(1) understands ISO8601 and RFC822 date formats. Also
remove references to cvs(1).

PR:		254894
MFC after:	3 days
Reported by:	danielsh@apache.org

usr.bin/find/find.1

@@ -31,7 +31,7 @@
 .\"	@(#)find.1	8.7 (Berkeley) 5/9/95
 .\" $FreeBSD$
 .\"
-.Dd May 13, 2021
+.Dd November 8, 2021
 .Dt FIND 1
 .Os
 .Sh NAME
@@ -659,8 +659,7 @@ In addition, if
 then
 .Ar file
 is instead interpreted as a direct date specification of the form
-understood by
-.Xr cvs 1 .
+understood by ISO8601 or RFC822.
 Note that
 .Ic -newermm
 is equivalent to
@@ -1001,7 +1000,6 @@ section below for details.
 .Sh SEE ALSO
 .Xr chflags 1 ,
 .Xr chmod 1 ,
-.Xr cvs 1 ,
 .Xr locate 1 ,
 .Xr lsvfs 1 ,
 .Xr whereis 1 ,