Improve help text for --scan

Improve the help text for --scan making it more verbose.

Signed-off-by: Peter Senna Tschudin <peter.senna@collabora.com>

tools/psdk

@@ -432,7 +432,8 @@ def main():
                                 storage.""".format(BKP_EXTENSION))
 
     etc_group.add_argument("-s", "--scan", action="store_true",
-                           help="""Scan persistent storage for configuration files and use them""")
+                           help="""Scan persistent storage for configuration files and configures
+                                the SDK to use each configuration file found.""")
 
     disk_group.add_argument("-c", "--configure", action="store_true",
                             help="""Configure this SDK to use use an already initialized disk for