split spi stuff in three part:
- v1 : basic spi peripheral
- v1_frf : v1 spi with frf mode additional bit in spi_cr2 / spi_sr
- v2 : spi with variable datasize, fifo and other fancy stuff.
v1 maps to f1 chips
v1_frf to f2, f4 and l0,l1
v2 to f0, f3 and l4
This breaks spi_master_init API for v2 devices : function prototype from
common spi header used to be abused, with DFF bit reused for CRCL bit.
New v2 spi_master_init does not handle anymore CRCL bits, as it does not
usually mess with other crc configuration.
