media: dvb: Change printouts from error to debug level

Some of the printouts with error level might be printed
for normal cases when DVR device or filter is closed while
filter data handler is still running. As these may happen
and do not cause a real error, printouts are changed
to debug level rather than error level.

Change-Id: Ic3b643b87aa73104d71678e5d654a39e2dc580b0
Signed-off-by: Hamad Kadmany <hkadmany@codeaurora.org>