Fix esp8266 pwm

[mikee47]

Fix bug introduced in #2752 where PWM doesn't initialise GPIO correctly. See #2888.

[what-the-diff]

PR Summary

• Removal of Peripheral Header File Inclusion
  The reference to "peripheral.h" in the pins_arduino.h file has been taken out. This is a good thing because it potentially decreases the complexity of the code and removes any unneeded dependencies, making the code more maintainable.

• Introduction of GPIO Pin Function Mapping Array
  An array named gpioPinFunc has been added to the HardwarePWM.cpp file. The purpose of this array is to define how the various GPIO (General Purpose Input Output) pins on the device should behave, specifically outlining which functions they should perform.

• Update to Pin Assignment Logic
  The way we assign functions to pins has been updated. Now, instead of using the old esp8266_gpioToFn[pin] mapping, we're using the new gpioPinFunc[pin] array introduced in this update. This should provide us with a more direct and efficient way of mapping functions to GPIO pins.