gas: Add macro tests for PR gas/32073

gas: Add macro tests for PR gas/32073

1. Add a macro test for expression argument with inner white spaces and
a white space before argument added by C preprocessor.
2. Add a x86-64 specific macro test.

	PR gas/32073
	* testsuite/gas/i386/x86-64-macro-1.d: New file.
	* testsuite/gas/i386/x86-64-macro-1.s: Likewise.
	* testsuite/gas/i386/x86-64.exp: Run x86-64-macro-1.
	* testsuite/gas/macros/arg1.d: New file.
	* testsuite/gas/macros/arg1.s: Likewise.
	* testsuite/gas/macros/macros.exp: Run arg1.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>