Mark InputDispatcher::dump as const

This helps debug InputDispatcher by dumping its state from other const functions.

Bug: 281806933
Test: none
Change-Id: Ic7f1cef7eeaa753115143756ce60f4167412ef24
diff --git a/services/inputflinger/dispatcher/InputDispatcher.cpp b/services/inputflinger/dispatcher/InputDispatcher.cpp
index 65bd05b..df3f7d9 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.cpp
+++ b/services/inputflinger/dispatcher/InputDispatcher.cpp
@@ -6590,7 +6590,7 @@
     }
 }
 
-void InputDispatcher::dump(std::string& dump) {
+void InputDispatcher::dump(std::string& dump) const {
     std::scoped_lock _l(mLock);
 
     dump += "Input Dispatcher State:\n";