[libFuzzer] Mark libFuzzer SIGTRAP test unsupported on windows

Author: DanBlackwell

compiler-rt/test/fuzzer/sig-trap.test

@@ -1,3 +1,7 @@
+# Check that libFuzzer handles SIGTRAP; disabled on Windows due to reliance on
+# posix only features
+UNSUPPORTED: target={{.*windows.*}}
+
 RUN: %cpp_compiler %S/SigTrapTest.cpp -o %t
 
 RUN: not %run %t            2>&1 | FileCheck %s