ath9k: fix debug print on regd

With debugging enabled and with ATH_DBG_REGULATORY
selected we wouldn't get the full print out of one line,
reason is we used "," instead of nothing to separate two
lines.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>