The set of regulators available in the PM8909 PMIC is similar to PM8916
which is already supported by the driver. s3, s4 and l16 are missing.
However, probing the SPMI hardware identification registers using the
qcom_spmi-regulator driver reveals that the regulators in PM8909 are
actually some kind of mixture between PM8916 and PM8226:

  - ult_lo_smps (= pm8916_buck_lvo_smps): s1
  - ult_ho_smps (= pm8916_buck_hvo_smps): s2
  - ult_nldo (= pm8916_nldo): l1, l2, l3, l10
  - ult_pldo (= pm8916_pldo): l4, l8, l9, l12-l15, l17, l18
  - pldo (= pm8226_pldo): l5, l6, l7, l11

Use this mapping to add the rpm_regulator_data for PM8909 by reusing
the existing regulator definitions.
Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Link: https://lore.kernel.org/r/20220623094614.1410180-4-stephan.gerhold@kernkonzept.comSigned-off-by: Mark Brown <broonie@kernel.org>