livemedia-creator: don't pass console=ttyS0

passing console=ttyS0 makes the virt hang until there is input. Remove
it and now it will run unattended in text mode.

src/sbin/livemedia-creator

@@ -284,8 +284,6 @@ class VirtualInstall( object ):
             extra_args += " "+kernel_args
         if iso.liveos:
             extra_args += " stage2=live:CDLABEL={0}".format(udev_escape(iso.label))
-        if not vnc:
-            extra_args += " console=ttyS0"
         cmd.append("--extra-args")
         cmd.append(extra_args)