xz: Update the man page that change to --keep will be in 5.2.6.

src/xz/xz.1

@@ -5,7 +5,7 @@
 .\" This file has been put into the public domain.
 .\" You can do whatever you want with this file.
 .\"
-.TH XZ 1 "2022-07-12" "Tukaani" "XZ Utils"
+.TH XZ 1 "2022-07-24" "Tukaani" "XZ Utils"
 .
 .SH NAME
 xz, unxz, xzcat, lzma, unlzma, lzcat \- Compress or decompress .xz and .lzma files
@@ -395,7 +395,7 @@ Don't delete the input files.
 .IP ""
 Since
 .B xz
-5.4.0,
+5.2.6,
 this option also makes
 .B xz
 compress or decompress even if the input is