swift

2354c7ce - Fix an ARMASM build error

Fix an ARMASM build error PUBLIC is a MASM directive and causes a build error in a certain version of MSVC ``` Microsoft (R) ARM Macro Assembler Version 14.44.35217.0 for 64 bits Copyright (C) Microsoft Corporation. All rights reserved. D:\r\_work\swift-build\swift-build\SourceCache\swift\stdlib\public\RuntimeModule\get-cpu-context-aarch64.asm(21) : error A2003: improper line syntax: PUBLIC ``` EXPORT is an ARMASM equivalent, which is already there.