hwmon: (axi-fan-control) remove duplicate macros

These macros are also present in the "include/linux/fpga/adi-axi-common.h"
file which is included in this driver.

This patch removes them from the AXI Fan Control driver. No sense in having
them in 2 places.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200803054311.98174-1-alexandru.ardelean@analog.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>