rp/spi: add write-only spi driver

embassy-rp/src/lib.rs

@@ -14,6 +14,7 @@ pub mod interrupt;
 
 pub mod dma;
 pub mod gpio;
+pub mod spi;
 pub mod uart;
 
 mod clocks;
@@ -60,6 +61,9 @@ embassy_extras::peripherals! {
     UART0,
     UART1,
 
+    SPI0,
+    SPI1,
+
     DMA_CH0,
     DMA_CH1,
     DMA_CH2,