gigaset: use pr_err() and pr_info()

Switch from private printk wrapper macros to using pr_err() and
pr_info() from linux/kernel.h, at the same time unifying a few
error messages.

Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
8 files changed