Add SPI slave constructors

Fix SPI slave constructors
Fix embedded hal async trait

One more constructor fix

Set SSM bit in SPI driver according to CommunicationMode

Fix embedded_hal_async trait to be generic for both master and slave

Fix I2S driver to use async master SPI

Forgot import from spi mode

Fix CommunicationMode associated const conditionals

Duplicate doc for CommunicationMode const

Add missing nss argument

Fix existing SPI tests not compiling

Fix stm32h7rs examples not compiling

Fix failing stm32l4 example

Fix stm32h7 example

Fix stm32h7 spi_bdma example

Fix stm32h7 spi example

Fix stm32f4 example

docs: added entry in changelog.md

fix: spi_v3 vals mismatch + rise_fall_speed renamed to gpio_speed
fix: added spi_v6 conditional compilation feature

fix: use if_afio macro in slave constructors
fix: add missing trait bound
fix: if_afio for cs pin trait

fix: changelog message

fix: broken rebase

Fixes #2902.