regulator: da9062: Remove unused variable build warning

Remove the unused variable build warning for reg_matches that appears
during the compilation of the DA9062 regulator driver.

da9062-regulator.c: In function da9062_regulator_probe:
da9062-regulator.c:727:29: warning: unused variable reg_matches

Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>