package/xfsprogs: bump version to 6.4.0

Patch 0003-libxfs-stop-overriding-MAP_SYNC-in-publicly-exported.patch is upstreamed.

See here for changes to the previous version:
https://fossies.org/linux/xfsprogs/doc/CHANGES

Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>