regulator: fan53555: fix wrong cast in probe

The vendor-id gathered from the dt match-data was cast to int but assigned
to an unsigned long, producing warnings on at least sparc, like

   drivers/regulator/fan53555.c: In function 'fan53555_regulator_probe':
>> drivers/regulator/fan53555.c:373:16: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
      di->vendor = (int) match->data;

Fix this by using an appropriate cast.

Reported-by: kbuild test robot
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>