fuse2fs: fix removing ea inodes when freeing a file

fuse2fs: fix removing ea inodes when freeing a file

If the filesystem has ea_inode set, then each file that has xattrs might
have stored an xattr value in a separate inode.  These inodes also need
to be freed, so create a library function to do that, and call it from
the fuse2fs unlink method.  Seen by ext4/026.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/174786677996.1383760.7408606469648643965.stgit@frogsfrogsfrogs
Signed-off-by: Theodore Ts'o <tytso@mit.edu>