InputMapper refactor: Change readerconfig pointer to const ref

We are refactoring Input-mapper to ensure they are configured at the
time of initialisation.

In this CL we are changing InputReaderConfiguration raw pointer to
a const reference and rename it to readerConfig for clarity.

Test: build, inputflinger_tests, presubmit checks

Bug: 256009910
Change-Id: Iae22c8cfba836bd311a51fca13d680456a61e604
diff --git a/services/inputflinger/reader/mapper/TouchInputMapper.cpp b/services/inputflinger/reader/mapper/TouchInputMapper.cpp
index c19737d..9a426bf 100644
--- a/services/inputflinger/reader/mapper/TouchInputMapper.cpp
+++ b/services/inputflinger/reader/mapper/TouchInputMapper.cpp
@@ -288,11 +288,11 @@
 }
 
 std::list<NotifyArgs> TouchInputMapper::reconfigure(nsecs_t when,
-                                                    const InputReaderConfiguration* config,
+                                                    const InputReaderConfiguration& config,
                                                     uint32_t changes) {
     std::list<NotifyArgs> out = InputMapper::reconfigure(when, config, changes);
 
-    mConfig = *config;
+    mConfig = config;
 
     // Full configuration should happen the first time configure is called and
     // when the device type is changed. Changing a device type can affect