Update wireless charging documentation val

Test: manual
Change-Id: I09b3d7b02907a2d3a05e3e32278b89f381952399
Fixes: 116150237
diff --git a/proto/src/metrics_constants/metrics_constants.proto b/proto/src/metrics_constants/metrics_constants.proto
index 41b3feb..a787c08 100644
--- a/proto/src/metrics_constants/metrics_constants.proto
+++ b/proto/src/metrics_constants/metrics_constants.proto
@@ -5922,7 +5922,7 @@
     // Tag used to determine what type of charging was started/ended
     // 1 = Plugged AC
     // 2 = Plugged USB
-    // 3 = Wireless
+    // 4 = Wireless
     FIELD_PLUG_TYPE = 1421;
 
     // ACTION: USB-C Connector connected.