regulator: isl6271a: Use NULL instead of 0
regulator: isl6271a: Use NULL instead of 0

init_data is a pointer. Use NULL instead of 0.

Silences the following sparse warning:
drivers/regulator/isl6271a-regulator.c:133:44:
warning: Using plain integer as NULL pointer

Signed-off-by: Sachin Kamat <1c3b1584a6008857f36c03c58f657c0fc16fc09e@linaro.org>
Signed-off-by: Mark Brown <b51b9a92386687a9ac927cebfa0f978adeb8cea5@opensource.wolfsonmicro.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs