[PATCH] Add FreeBSD support to the address sanitizer's waitid.cc test case

[Alexey Samsonov]

LGTM

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Comment at: test/asan/TestCases/Posix/waitid.cc:7
@@ -6,2 +6,3 @@
 #include <unistd.h>
+#include <signal.h>
 
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Please sort the includes (unless this order is necessary for FreeBSD).

http://reviews.llvm.org/D4422