hwmon: (f75375s) Fix bit shifting in f75375_write16

In order to extract the high byte of the 16-bit word, shift the word to
the right, not to the left.

Signed-off-by: Nikolaus Schulz <mail@microschulz.de>
Cc: stable@kernel.org # 2.6.32+
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>