mkarchiso: remove unneeded workarounds in _mkairootfs_ext4+squashfs

* Do not run `tune2fs` on the image. The file system is not mounted, so
the default values for "Maximum mount count" (`tune2fs` option `-c`) and
"Check interval" (`tune2fs` option `-i`) are fine as is. With this change
the ext4 image is reproducible.
* Remove `E2FSPROGS_FAKE_TIME`. e2fsprogs 1.47.1 supports
`SOURCE_DATE_EPOCH` so setting this e2fsprogs specific variable is not needed
anymore.
See https://github.com/tytso/e2fsprogs/issues/131 for details.

CHANGELOG.rst

@@ -22,6 +22,8 @@ Fixed
 Removed
 -------
 
+- Remove unneeded workaround for e2fsprogs < 1.47.1.
+
 [78] - 2024-05-23
 =================
 

archiso/mkarchiso

@@ -202,8 +202,7 @@ _mkairootfs_ext4+squashfs() {
     )
     [[ ! "${quiet}" == "y" ]] || mkfs_ext4_options+=('-q')
     rm -f -- "${pacstrap_dir}.img"
-    E2FSPROGS_FAKE_TIME="${SOURCE_DATE_EPOCH}" mkfs.ext4 "${mkfs_ext4_options[@]}" -- "${pacstrap_dir}.img" 32G
-    tune2fs -c 0 -i 0 -- "${pacstrap_dir}.img" >/dev/null
+    mkfs.ext4 "${mkfs_ext4_options[@]}" -- "${pacstrap_dir}.img" 32G
     _msg_info "Done!"
 
     install -d -m 0755 -- "${isofs_dir}/${install_dir}/${arch}"