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/services/inputflinger/reader/mapper/TouchInputMapper.h b/services/inputflinger/reader/mapper/TouchInputMapper.h
index 8451675..9b7fe93 100644
--- a/services/inputflinger/reader/mapper/TouchInputMapper.h
+++ b/services/inputflinger/reader/mapper/TouchInputMapper.h
@@ -589,6 +589,8 @@
 
             // Waiting for quiet time to end before starting the next gesture.
             QUIET,
+
+            ftl_last = QUIET,
         };
 
         // When a gesture is sent to an unfocused window, return true if it can bring that window