input: fix -Wformat warnings

These occur when an enum value is formatted as an integer without a
cast. In all these cases the debug logs are nicer if we use the actual
name of the enum value, so wrap them all in ftl::enum_string calls.

Bug: 245989146
Test: Check there are no -Wformat warnings in the output of
      $ m checkinput
Change-Id: I26333123e9fb445f1640c5e73757ddf4ad2d6e98
diff --git a/include/input/InputDevice.h b/include/input/InputDevice.h
index 57b659d..d7aeb31 100644
--- a/include/input/InputDevice.h
+++ b/include/input/InputDevice.h
@@ -115,6 +115,8 @@
     ACCURACY_LOW = 1,
     ACCURACY_MEDIUM = 2,
     ACCURACY_HIGH = 3,
+
+    ftl_last = ACCURACY_HIGH,
 };
 
 enum class InputDeviceSensorReportingMode : int32_t {