x86: Add {load}/{store} tests for apx instructions.

gas/ChangeLog:

        * testsuite/gas/i386/x86-64.exp: Add {load}/{store} tests for apx
	instructions.
        * testsuite/gas/i386/x86-64-pseudos-apx.d: New test.
        * testsuite/gas/i386/x86-64-pseudos-apx.s: Ditto.
3 files changed