Add pwr for L1 and update RCC to new reg block

embassy-stm32/src/pwr/l1.rs

@@ -0,0 +1 @@
+

embassy-stm32/src/pwr/mod.rs

@@ -2,6 +2,7 @@
 #[cfg_attr(pwr_f4, path = "f4.rs")]
 #[cfg_attr(pwr_wl5, path = "wl5.rs")]
 #[cfg_attr(pwr_g0, path = "g0.rs")]
+#[cfg_attr(pwr_l1, path = "l1.rs")]
 mod _version;
 
 pub use _version::*;