More cases where libc should use O_CLOEXEC.

Change-Id: Idfa111aeebc5deca2399dae919e8b72eb54c23c0
diff --git a/libc/bionic/malloc_debug_qemu.cpp b/libc/bionic/malloc_debug_qemu.cpp
index b3b604d..2f4949b 100644
--- a/libc/bionic/malloc_debug_qemu.cpp
+++ b/libc/bionic/malloc_debug_qemu.cpp
@@ -606,7 +606,7 @@
      * the memory mapped spaces into writes to an I/O port that emulator
      * "listens to" on the other end. Note that until we open and map that
      * device, logging to emulator's stdout will not be available. */
-    int fd = open("/dev/qemu_trace", O_RDWR);
+    int fd = open("/dev/qemu_trace", O_CLOEXEC | O_RDWR);
     if (fd < 0) {
         error_log("Unable to open /dev/qemu_trace");
         return false;