Increase in the full path to mkfs.xfs(/sbin/mkfs.xfs).

Xfsprogs package has been installed. This is the cause of the error stack does not have
permission to perform mkfs.xfs command rather mkfs.xfs command in /sbin/
path, stack in order to perform mkfs.xfs must add the full path or use
the sudo command mode.

Fixed bug #1292466

Change-Id: I488133539331b4a0034a2afb4e75665904754245
diff --git a/lib/swift b/lib/swift
index 26ee7d6..3e183ff 100644
--- a/lib/swift
+++ b/lib/swift
@@ -489,7 +489,7 @@
     truncate -s ${SWIFT_LOOPBACK_DISK_SIZE} ${SWIFT_DISK_IMAGE}
 
     # Make a fresh XFS filesystem
-    mkfs.xfs -f -i size=1024  ${SWIFT_DISK_IMAGE}
+    /sbin/mkfs.xfs -f -i size=1024  ${SWIFT_DISK_IMAGE}
 
     # Mount the disk with mount options to make it as efficient as possible
     mkdir -p ${SWIFT_DATA_DIR}/drives/sdb1