MTP: Add missing call to closedir() in recursive delete code

BUG: 3185660

Change-Id: I3744d2cb193829d20a689af2aea50e8516779631
Signed-off-by: Mike Lockwood <lockwood@android.com>
diff --git a/media/mtp/MtpServer.cpp b/media/mtp/MtpServer.cpp
index f74f395..5ba6be9 100644
--- a/media/mtp/MtpServer.cpp
+++ b/media/mtp/MtpServer.cpp
@@ -736,6 +736,7 @@
             unlink(pathbuf);
         }
     }
+    closedir(dir);
 }
 
 static void deletePath(const char* path) {