stm32: generate singletons only for pins that actually exist.

Before we'd generate all pins Px0..Px15 for each GPIOx port. This changes
codegen to only generate singletons for actually-existing pins.

(AFs were already previously filtered, so these non-existing pins were already mostly useless)

1 files changed, 2 insertions, 1 deletions

diff --git a/examples/stm32u5/src/bin/blinky.rs b/examples/stm32u5/src/bin/blinky.rs
index 7fe88c183..1fdfc7679 100644
--- a/examples/stm32u5/src/bin/blinky.rs
+++ b/examples/stm32u5/src/bin/blinky.rs
@@ -12,7 +12,8 @@ async fn main(_spawner: Spawner) -> ! {
     let p = embassy_stm32::init(Default::default());
     info!("Hello World!");
 
-    let mut led = Output::new(p.PH7, Level::Low, Speed::Medium);
+    // replace PC13 with the right pin for your board.
+    let mut led = Output::new(p.PC13, Level::Low, Speed::Medium);
 
     loop {
         defmt::info!("on!");