adb: don't spew to logcat when tracing is enabled.

When persist.adb.trace_mask is used to enable verbose logging, avoid
exponential logging when a user runs `adb logcat`. As a side-effect,
set the minimum logging level to include everything when ADB_TRACE is
used on the client (which is something we want anyway).

Bug: http://b/72971016
Test: `adb shell 'setprop persist.adb.trace_mask; killall adbd'; adb logcat`
Change-Id: Id4bca1f3933a920345499dbeaeb103c8a2e220cd
diff --git a/adb/adb_trace.h b/adb/adb_trace.h
index fc6560c..1d2c8c7 100644
--- a/adb/adb_trace.h
+++ b/adb/adb_trace.h
@@ -43,11 +43,11 @@
 #define VLOG_IS_ON(TAG) \
     ((adb_trace_mask & (1 << (TAG))) != 0)
 
-#define VLOG(TAG)         \
+#define VLOG(TAG)                 \
     if (LIKELY(!VLOG_IS_ON(TAG))) \
-        ;                 \
-    else                  \
-        LOG(INFO)
+        ;                         \
+    else                          \
+        LOG(DEBUG)
 
 // You must define TRACE_TAG before using this macro.
 #define D(...) \