[Libomptarget] Add missing include to define `printf`

Summary:
This test was failing because of an implicit declaration of `printf`
which isn't legal with newer C, causing it to fail. This patch just adds
the necessary header.

diff --git a/openmp/libomptarget/test/env/base_ptr_ref_count.c b/openmp/libomptarget/test/env/base_ptr_ref_count.c
index 975e134..bd2166e 100644 (file)
--- a/openmp/libomptarget/test/env/base_ptr_ref_count.c
+++ b/openmp/libomptarget/test/env/base_ptr_ref_count.c
@@ -2,6 +2,7 @@
 // REQUIRES: libomptarget-debug
 
 #include <stdlib.h>
+#include <stdio.h>
 
 int *allocate(size_t n) {
   int *ptr = malloc(sizeof(int) * n);