media: dvb-pll: fix tuner frequency ranges

Tuners should report frequencies in Hz. That works fine on most
drivers, but, in the case of dvb-pll, some settings are for
satellite tuners, while others are for terrestrial/cable ones.

The code was trying to solve it at probing time, but that doesn't
work, as, when _attach is called, the delivery system may be wrong.

Fix it by ensuring that all frequencies are in Hz at the per-tuner
max/min values.

While here, add a debug message, as this would help to debug any
issues there.

It partially fixes the following bug:
  https://bugzilla.opensuse.org/show_bug.cgi?id=1116374

Fixes: a3f90c75

 ("media: dvb: convert tuner_info frequencies to Hz")
Reported-by: Stakanov Schufter <stakanov@eclipso.eu>
Reported-by: Takashi Iwai <tiwai@suse.de>
Cc: stable@vger.kernel.org # For 4.19
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>