Add embassy-cortex-m crate.

- Move Interrupt and InterruptExecutor from `embassy` to `embassy-cortex-m`.
- Move Unborrow from `embassy` to `embassy-hal-common` (nothing in `embassy` requires it anymore)
- Move PeripheralMutex from `embassy-hal-common` to `embassy-cortex-m`.

embassy-macros/src/lib.rs

@@ -22,16 +22,20 @@ pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
 }
 
 #[proc_macro_attribute]
-pub fn interrupt(args: TokenStream, item: TokenStream) -> TokenStream {
+pub fn cortex_m_interrupt(args: TokenStream, item: TokenStream) -> TokenStream {
     let args = syn::parse_macro_input!(args as syn::AttributeArgs);
     let f = syn::parse_macro_input!(item as syn::ItemFn);
-    interrupt::run(args, f).unwrap_or_else(|x| x).into()
+    cortex_m_interrupt::run(args, f)
+        .unwrap_or_else(|x| x)
+        .into()
 }
 
 #[proc_macro]
-pub fn interrupt_declare(item: TokenStream) -> TokenStream {
+pub fn cortex_m_interrupt_declare(item: TokenStream) -> TokenStream {
     let name = syn::parse_macro_input!(item as syn::Ident);
-    interrupt_declare::run(name).unwrap_or_else(|x| x).into()
+    cortex_m_interrupt_declare::run(name)
+        .unwrap_or_else(|x| x)
+        .into()
 }
 
 /// # interrupt_take procedural macro
@@ -40,7 +44,9 @@ pub fn interrupt_declare(item: TokenStream) -> TokenStream {
 /// We are aware that this brings bloat in the form of core::fmt, but the bloat is already included with e.g. array indexing panics.
 /// To get rid of this bloat, use the compiler flags `-Zbuild-std=core -Zbuild-std-features=panic_immediate_abort`.
 #[proc_macro]
-pub fn interrupt_take(item: TokenStream) -> TokenStream {
+pub fn cortex_m_interrupt_take(item: TokenStream) -> TokenStream {
     let name = syn::parse_macro_input!(item as syn::Ident);
-    interrupt_take::run(name).unwrap_or_else(|x| x).into()
+    cortex_m_interrupt_take::run(name)
+        .unwrap_or_else(|x| x)
+        .into()
 }