avr: added initial module to handle reed contacts.

Detects and reports opening and closing of a window/door.
Nexts step is to allow for external configuration (e.g. standard mode
with one reed contact versus multi-contact mode to detect tilting of a
window/door).

avr/main.asm

@@ -140,6 +140,10 @@ initModules:
   rcall CNY70_Init
 #endif
 
+#ifdef MODULES_REED
+  rcall REED_Init
+#endif
+
   ; done
   ret
 
@@ -181,6 +185,10 @@ runModulesUntilIdle_ComEnd:
   rcall Stats_Run
 #endif
 
+#ifdef MODULES_REED
+  rcall REED_Run
+#endif
+
   ; add more modules here
   ret