[bsp/n32g452xx] Unified header file definition. "GPIO_H__" to "DRV_GPIO_H". "USART_H" to "DRV_USART_H"
[bsp/n32g452xx] In drv_pwm.c, variable meaning is different with RT-Thread interface definition. Fixed and tested.
[bsp/n32g452xx] Add support for UART4/UART5.
[bsp/n32g452xx] In drv_gpio.c Modify "N32F10X_PIN_NUMBERS" to "N32G45X_PIN_NUMBERS".

1. add tim1/2/3/4/5/8 pwm driver and test pass by self.

[AT32] 完善ADC驱动

1. Calibration is required when ADC is enabled, and calibration is not required when enabling
ADC.
2. format code style

[add] N32G452 BSP

1. 添加PWM测试代码
2. 修正PWM驱动周期与脉冲错误问题

1. ref https://github.com/mysterywolf/formatting

1. 部分驱动已经整改,但未验证
2. 根据AT32整改目录结构

1. modify at32_msp default configuration 2. add hwtimer driver and fix up some driver errors 3. update related files