Add the log of starting idmap2d back

When IdmapDaemon calls kernel to start idmap2d, there is some unknown
exception happened. And, we need the exception log back to triage the
root cause well.

Bug: 232351707

Test: atest OverlayHostTests OverlayDeviceTests OverlayRemountedTest

Change-Id: I0fe533061c1ed4db03156cd4a055e8611611026a

services/core/java/com/android/server/om/IdmapDaemon.java

@@ -267,8 +267,8 @@ class IdmapDaemon {
         try {
             SystemService.start(IDMAP_DAEMON);
         } catch (RuntimeException e) {
+            Slog.wtf(TAG, "Failed to enable idmap2 daemon", e);
             if (e.getMessage().contains("failed to set system property")) {
-                Slog.w(TAG, "Failed to enable idmap2 daemon", e);
                 return null;
             }
         }