Merge #914

914: (embassy-rp): Add I2C master implementation r=Dirbaio a=MathiasKoch

This PR adds both blocking and DMA based async implementations of I2C master.

Both E-H 0.2 & E-H 1.0 abstractions are implemented as well.

### Questions & concerns:
- Do we need an I2C interrupt handler (for transfer done, abort & error handling?) (async only)
- Do we need to add some automatic attempt at unblocking an I2C bus in case of failures (see ref: https://github.com/fivdi/pico-i2c-dma/blob/7ebfd553f3ce5b5b210d53102b0ecca158172633/src/i2c_dma.c#L116-L142

)
- Should I add `vectored_{read, write}` implementations?

Co-authored-by: Mathias <mk@blackbird.online>
Co-authored-by: Mathias Koch <mk@blackbird.online>