Exclude apple from assembly test

Author: scottmcm

tests/assembly/x86_64-array-pair-load-store-merge.rs

@@ -2,6 +2,7 @@
 // compile-flags: --crate-type=lib -O -C llvm-args=-x86-asm-syntax=intel
 // only-x86_64
 // ignore-sgx
+// ignore-macos (manipulates rsp too)
 
 // Depending on various codegen choices, this might end up copying
 // a `<2 x i8>`, an `i16`, or two `i8`s.