staging: wilc1000: wilc_wfi_cfgoperations.c: replaces PRINT_ER with netdev_err

This patches replaces PRINT_ER with netdev_err.
Removes unnecessary debug logs as well.

Signed-off-by: Leo Kim <leo.kim@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>