regulator: dummy: Constify dummy_initdata and dummy_ops

regulator: dummy: Constify dummy_initdata and dummy_ops

The only usage of dummy_initdata is to assign its address to the
init_data field of the regulator_config struct and the only usage
dummy_ops is to assign its address to the ops field in the
regulator_desc struct, both which are const pointers. Make them const to
allow the compiler to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20200913084114.8851-2-rikard.falkeborn@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>