hwmon: (w83627ehf) Force initial bank selection

Don't assume bank 0 is selected at device probe time. This may not be
the case. Force bank selection at first register access to guarantee
that we read the right registers upon driver loading.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org