GPIO driver

[cepetr]

Introduce a custom GPIO driver with a better abstraction tailored to our specific needs. This interface aims to simplify GPIO handling and improve code clarity while resolving issues like duplicated initialization in RCC.

The following is an initial idea/proposal for further discussion:

Initialization/deinitialization with reference counting and automatic clock enabling/disabling (similar to i2c_bus approach):

gpio_pin_t gpio_pin_open(uint32_t port, uint8_t pin, const gpio_pin_config_t* config);
void gpio_pin_close(gpis_port_t pin);

A routine for pin configuration:

typedef struct {
   mode;
   pull;
   speed;
   altfunc;
} gpio_pin_config_t;

void gpio_pin_configure(gpio_pin_t pin, const gpio_pin_config_t* config);

and introduce few constant with typical gpio configuration:

GPIO_PIN_INPUT
GPIO_PIN_INPUT_PU
GPIO_PIN_OUTPUT_PP
GPIO_PIN_OUTPUT_OD
GPIO_PIN_ANALOG

Read and write routines

void gpio_pin_write(gpio_pin_t pin);
void gpio_pin_set(gpio_pin_t pin);
void gpio_pin_reset(gpio_pin_t pin);
bool gpio_pin_read(gpio_pin_t pin);