support: Use support_record_failure consistently

This causes more test programs to link in the support_record_failure
function, which triggers an early call to mmap from an ELF
constructor, but this should not have side effects intefering
with the functionality actually under test (unlike, say, a call
to malloc).

support/support_record_failure.c

@@ -36,8 +36,8 @@
    propagate to the parent process.  */
 struct test_failures
 {
-  unsigned counter;
-  unsigned failed;
+  unsigned int counter;
+  unsigned int failed;
 };
 static struct test_failures *state;