[PATCH] isdn4linux: Siemens Gigaset drivers: logging usage

With Hansjoerg Lipp <hjlipp@web.de>

Improve error reporting of the Gigaset drivers, by using the
dev_err/dev_warn/dev_info macros from device.h instead of err/warn/info from
usb.h whereever possible.

Also rename the private dbg macro to gig_dbg in order to avoid confusion with
the macro of the same name in usb.h.

Signed-off-by: Hansjoerg Lipp <hjlipp@web.de>
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>