[XRay][compiler-rt] Only run test in x86_64 linux.
Followup to D34669.
// RUN: FileCheck %s --check-prefix NOINSTR
// RUN: %llvm_xray extract -symbolize %t | \
// RUN: FileCheck %s --check-prefix ALWAYSINSTR
+// REQUIRES: x86_64-linux
+// REQUIRES: built-in-llvm-tree
// NOINSTR-NOT: {{.*__xray_NeverInstrumented.*}}
int __xray_NeverInstrumented() {
