[fuzzer] Disable uncaught-exception on non-Win+undo bad fix

Test is failing on non-Windows platforms. Also undo speculative
fix since it causes failures on Windows.

Author: jonathanmetzman

compiler-rt/test/fuzzer/uncaught-exception.test

@@ -1,8 +1,10 @@
 # Test that throws a C++ exception and doesn't catch it. Should result in a
 # crash
+# FIXME: Get test working on other platforms.
+REQUIRES: windows
 RUN: %cpp_compiler %S/UncaughtException.cpp -o %t-UncaughtException
 
-RUN: ASAN_OPTIONS=allocator_may_return_null=1 not %run %t-UncaughtException 2>&1 | FileCheck %s
+RUN: not %run %t-UncaughtException 2>&1 | FileCheck %s
 
 CHECK: ERROR: libFuzzer: deadly signal
 CHECK: Test unit written to ./crash