* fix(fmu-v6c): correct GPIO_VDD_3V3_SENSORS_EN macro name
VDD_3V3_SENSORS_EN() referenced GPIO_VDD_3V3_SENSORS4_EN which
does not exist. The correct macro is GPIO_VDD_3V3_SENSORS_EN.
Fixes#26454
* fix(boards): rename VDD_3V3_SENSORS4_EN to VDD_3V3_SENSORS_EN
These boards have a single sensor power rail that was incorrectly
named SENSORS4_EN (copy-paste from boards with 4 rails). Rename
to SENSORS_EN to match the actual hardware.
Boards with legitimately numbered rails (fmu-v6xrt, x25-evo,
x25-super) are not changed.
