Remove unneeded workaround from stm32f1
Make pullup configurable
Fix OAR1 register initialization
improve i2c read functions with repeatead start conditions
avoid to any loop to become infinite
improve i2c driver error handling
add missing coma in array initializers
Add missing DMA interrupts for UART
Improve baudrate intialization:
- Return error if baudrate is theorically unreachable
- Implement oversampling by 8 method for high baudrates
Add UART hardware flow control support
Ensure uart tx thread safety with a mutex
Allow setting of pins mode per UART