regulator: da9063: Add missing initialization of da9063_reg_matches

With gcc 4.1.2:

drivers/regulator/da9063-regulator.c: In function ‘da9063_regulator_probe’:
drivers/regulator/da9063-regulator.c:847: warning: ‘da9063_reg_matches’ is used
uninitialized in this function

If the parent device already has platform data, da9063_reg_matches will
not be initialized.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>