Remove address-of operator ('&') when assigning `gpio_xxx_init`
function pointer in `DEVICE_DT_INST_DEFINE` macro.
This change aims to maintain consistency among the drivers in
`drivers/gpio`, ensuring that all function pointer assignments
follow the same pattern.
Signed-off-by: Pisit Sawangvonganan <pisit@ndrsolution.com>
Only provide implementations for optional operations if needed. This
patch deletes quite a few dummy `pin_interrupt_configure` ops (now
optional), and adjusts ifdeffery on some drivers so that optional ops
are only provided if they implement real functionality.
Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>