Refactoring keys/switches/trims in simu (#6515)

Refactoring keys/switches/trims in simu

radio/src/targets/taranis/keys_driver.cpp

@@ -100,7 +100,7 @@ uint32_t readTrims()
   return result;
 }
 
-uint8_t trimDown(uint8_t idx)
+bool trimDown(uint8_t idx)
 {
   return readTrims() & (1 << idx);
 }
@@ -168,11 +168,6 @@ void readKeysAndTrims()
       } \
       break
 
-uint8_t keyState(uint8_t index)
-{
-  return keys[index].state();
-}
-
 #if !defined(BOOT)
 uint32_t switchState(uint8_t index)
 {