Extend help for --updates and --ks parameters

Give user an information that this will automatically add relevant
kernel boot options to the kernel command line. This is mainly to avoid
issues that user doesn't have to specify this again.

src/bin/mkksiso

@@ -560,9 +560,9 @@ def setup_arg_parser():
     parser.add_argument("--no-md5sum", action="store_false", default=True,
                         help="Do not run implantisomd5 on the ouput iso")
     parser.add_argument("--ks", type=os.path.abspath, metavar="KICKSTART",
-                        help="Optional kickstart to add to the ISO")
+                        help="Optional kickstart to add to the ISO (adding inst.ks automatically)")
     parser.add_argument("-u", "--updates", type=os.path.abspath, metavar="IMAGE",
-                        help="Optional updates image to add to the ISO")
+                        help="Optional updates image to add to the ISO (adding inst.updates automatically)")
     parser.add_argument("-V", "--volid", dest="volid", help="Set the ISO volume id, defaults to input's", default=None)
     parser.add_argument("-R", "--replace", nargs=2, action="append", metavar=("FROM", "TO"),
                         help="Replace string in grub.cfg. Can be used multiple times")