regulator: dt-bindings: dlg,da9121: Add dlg,no-gpio-control

regulator: dt-bindings: dlg,da9121: Add dlg,no-gpio-control

Add the optional boolean property dlg,no-gpio-control. When present, it
indicates that no DA91xx GPIO pins are configured/used with functions
RELOAD/DVC/EN, which can affect the output voltage control, regulator
mode control and enable signal control.

The absence of relevant GPIO DT properties does not imply that the
RELOAD/DVC/EN GPIO functions are unused. These functions are provided by
DA91xx GPIO pins and may be controlled by external hardware without
corresponding GPIO DT properties. The dlg,no-gpio-control property
explicitly indicates that none of these GPIO functions are used.

It is mutually exclusive with enable-gpios, regardless of whether the
referenced GPIO is connected to a GPIO pin or the IC_EN pin, since
enable-gpios allows the regulator to be controlled via an external
hardware signal.

Co-developed-by: Waqar Hameed <waqar.hameed@axis.com>
Signed-off-by: Waqar Hameed <waqar.hameed@axis.com>
Signed-off-by: André Svensson <andre.svensson@axis.com>
Link: https://patch.msgid.link/20260320-no-gpio-control-v2-1-dbc938e462cb@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>