Documented a public external value

Author: mhahnFr

include/callstack_internals.h

@@ -29,6 +29,9 @@ extern "C" {
 #endif
 
 #ifdef LCS_ACTIVATE_SWIFT_DEMANGLER_CONTROL
+/**
+ * Whether to use the Swift demangler if necessary and available.
+ */
 extern bool lcs_activateSwiftDemangler;
 #endif
 
@@ -49,7 +52,7 @@ extern bool callstack_autoClearCaches;
 /**
  * @brief Clears the caches of this library.
  *
- * Only needs to be called when `callstack_autoClearCaches` is `false`.
+ * Only needs to be called when @c callstack_autoClearCaches is @c false .
  *
  * @since v1.1
  */