[COMMITTED PATCH] gdb.threads/thread-execl.exp: #include <stdio.h>.

[Doug Evans]

Hi.

clang was complaining:

      implicit declaration of function 'perror' is invalid in C99
      [-Wimplicit-function-declaration]
      perror ("execl");

Committed.

2014-08-25  Doug Evans  <dje@google.com>

	* gdb.threads/thread-execl.exp: #include <stdio.h>.

diff --git a/gdb/testsuite/gdb.threads/thread-execl.c b/gdb/testsuite/gdb.threads/thread-execl.c
index f8027ba..28ad23f 100644
--- a/gdb/testsuite/gdb.threads/thread-execl.c
+++ b/gdb/testsuite/gdb.threads/thread-execl.c
@@ -18,6 +18,7 @@
 #include <pthread.h>
 #include <unistd.h>
 #include <stdlib.h>
+#include <stdio.h>
 
 static const char *image;