[XRay] Only run shared tests when 'enable_shared' is true

Follow-up to D38226.

llvm-svn: 314191
diff --git a/clang/test/Driver/XRay/xray-shared-noxray.cpp b/clang/test/Driver/XRay/xray-shared-noxray.cpp
index e6dd7e6..19e526a 100644
--- a/clang/test/Driver/XRay/xray-shared-noxray.cpp
+++ b/clang/test/Driver/XRay/xray-shared-noxray.cpp
@@ -6,7 +6,7 @@
 // SHARED-NOT: {{clang_rt\.xray-}}
 // STATIC: {{clang_rt\.xray-}}
 //
-// REQUIRES: linux
+// REQUIRES: linux, enable_shared
 int foo() { return 42; }
 
 #ifdef MAIN