drivers/telephony/ixj: cleanup and fix gcc warning

1) Fix gcc uninit'd var warnings by adding 'default' switch stmt labels
in two cases.  It was lightning-strikes unlikely that a problem would
ever arise, but not impossible.

2) Tighten the scope of 'blankword' in two cases.

Signed-off-by: Jeff Garzik <jeff@garzik.org>