Update test comment

Author: thurstond

llvm/test/CodeGen/AArch64/hwasan-zero-ptr.ll

@@ -1,10 +1,11 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
 ; RUN: llc -filetype asm -o - %s | FileCheck %s
 
-; This shows that HWASan will elide the tag check when lowering the memaccess
-; intrinsic for null pointers.
+; This shows that CodeGen for AArch64 will elide the tag check when lowering
+; the HWASan memaccess intrinsic for null pointers.
+;
 ; N.B. The HWASan pass will normally omit the memaccess intrinsic if the
-; pointer is already statically known to be null.
+;      pointer is already statically known to be null.
 ;
 ; The source was generated from llvm/test/Instrumentation/HWAddressSanitizer/zero-ptr.ll
 ; with the memaccess deliberately retained.