Fix handling of MTP fork/child process

Change-Id: Iacd8a38d21e9c8b0dfafefbeb646f46cd3ba02a1
diff --git a/mtp/twrpMtp.cpp b/mtp/twrpMtp.cpp
index e7c3f2c..9a7df5b 100755
--- a/mtp/twrpMtp.cpp
+++ b/mtp/twrpMtp.cpp
@@ -99,6 +99,8 @@
 	if (pid == 0) {
 		// Child process
 		start();
+		MTPD("MTP child process exited.\n");
+		_exit(0);
 	} else {
 		return pid;
 	}