Add binding doc and driver.

DTS part wait for
https://lore.kernel.org/imx/Z04W5chGq5TitB9f@lizhi-Precision-Tower-5810/

Signed-off-by: Frank Li <Frank.Li@nxp.com>
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Changes in v2:
- Reuse nxp,pca9450-regulator.yaml. Add nxp,pf9453 in nxp,pca9450-regulator.yaml
instead of create new one.
- Link to v1: https://lore.kernel.org/r/20241206-pf9453-v1-0-1e4685114271@nxp.com

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Frank Li (1):
      regulator: dt-bindings: pca9450: Add nxp,pf9453 compatible string

Joy Zou (1):
      regulator: pf9453: add PMIC PF9453 support

 .../bindings/regulator/nxp,pca9450-regulator.yaml  |  24 +-
 drivers/regulator/Kconfig                          |   7 +
 drivers/regulator/Makefile                         |   1 +
 drivers/regulator/pf9453-regulator.c               | 723 +++++++++++++++++++++
 drivers/regulator/pf9453.h                         | 171 +++++
 5 files changed, 925 insertions(+), 1 deletion(-)
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base-commit: 0768222687cbdbe7c300c4428f0c0c6b153386e3
change-id: 20241205-pf9453-90e8dbda562a

Best regards,
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Frank Li <Frank.Li@nxp.com>