Btrfs-progs: add restore command's -x flag to man page

This is a recent flag added to the restore command that allows to restore xattrs. It was missing in the man page.

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NOTE: this patch is based on top of David Sterba's integration

      branch integration-20130810.

 man/btrfs.8.in |    2 ++
 1 file changed, 2 insertions(+)

index d493d7e..1993af5 100644
@@ -521,6 +521,8 @@ Try to restore files from a damaged filesystem(unmounted).
 \fIOptions\fR
 .IP "\fB-s\fP" 5
 get snapshots.
+.IP "\fB-x\fP" 5
+get extended attributes.
 .IP "\fB-v\fP" 5
 verbose.
 .IP "\fB-i\fP" 5

1.7.9.5