[libc++] Fix XFAILs when exceptions are disabled

It turns out that I un-XFAILed too many tests in r353210: some tests
actually fail whether exceptions are enabled or not because they use
types that are marked as unavailable even when exceptions are disabled.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@353215 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/utilities/optional/optional.bad_optional_access/default.pass.cpp

@@ -8,7 +8,7 @@
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 
-// XFAIL: dylib-has-no-bad_optional_access && !libcpp-no-exceptions
+// XFAIL: dylib-has-no-bad_optional_access
 
 // <optional>
 

test/std/utilities/optional/optional.bad_optional_access/derive.pass.cpp

@@ -7,7 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
-// XFAIL: dylib-has-no-bad_optional_access && !libcpp-no-exceptions
+// XFAIL: dylib-has-no-bad_optional_access
 
 // <optional>
 

test/std/utilities/variant/variant.bad_variant_access/bad_variant_access.pass.cpp

@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 
-// XFAIL: dylib-has-no-bad_variant_access && !libcpp-no-exceptions
+// XFAIL: dylib-has-no-bad_variant_access
 
 
 // <variant>