char *platform_pin_signal_name(int pin);
platform_pin_signal_name returns the signal name for pin pin. The signal name returned is generally the name from the schematic or, in the case of buttons and LEDs, the name of the button or LED on the silkscreen.
The string may be overwritten by a subsequent call to platform_pin_signal_name.
Special signal names, such as PLATFORM_NO_CONNECTION, are handled by platform_pin_signal_name and any platform-specific pins are passed to platform_private_pin_signal_name to handle.