UBUNTU: SAUCE: aufs: bugfix, for v4.10, copy-up on XFS branch

UBUNTU: SAUCE: aufs: bugfix, for v4.10, copy-up on XFS branch

BugLink: http://bugs.launchpad.net/bugs/1709749
The commit for linux-v4.10
	6552321 2016-11-30 xfs: remove i_iolock and use i_rwsem in the
				VFS inode instead
broke aufs' copy-up because XFS acquires inode_lock for a normal read().
Additionally XFS has its version and older one doesn't support
clone_file_range().
This commit fixes the error path after trying clone_file_range().

Reported-by: Vasily Tarasov <tarasov@vasily.name>
See-also: http://www.mail-archive.com/aufs-users@lists.sourceforge.net/msg05498.html
Signed-off-by: J. R. Okajima <hooanon05g@gmail.com>
(cherry picked from commit e34c81ff96415c64ca827ec30e7935454d26c1d3
 https://github.com/sfjro/aufs4-standalone.git)
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>