liblog: switch event_tag_map.c to event_tag_map.cpp

NB: recent activities on event_tag_map.c were to allow
    this transition to be unremarkable.

Test: compile
Bug: 31456426
Change-Id: I13e1771a001874244711a5ac3023861c2a5f8c7d
diff --git a/liblog/Android.bp b/liblog/Android.bp
index c498153..e59a460 100644
--- a/liblog/Android.bp
+++ b/liblog/Android.bp
@@ -27,7 +27,7 @@
     "fake_writer.c",
 ]
 liblog_target_sources = [
-    "event_tag_map.c",
+    "event_tag_map.cpp",
     "config_read.c",
     "log_time.cpp",
     "log_is_loggable.c",
@@ -68,7 +68,7 @@
             enabled: true,
         },
         not_windows: {
-            srcs: ["event_tag_map.c"],
+            srcs: ["event_tag_map.cpp"],
         },
         linux: {
             host_ldlibs: ["-lrt"],
diff --git a/liblog/event_tag_map.c b/liblog/event_tag_map.cpp
similarity index 100%
rename from liblog/event_tag_map.c
rename to liblog/event_tag_map.cpp