[GAS][ARM] Fix failing Armv1 test

[GAS][ARM] Fix failing Armv1 test

This test has been failing for a while and it could be argued that since we
started testing 'arm7t' here (and not Armv1) the test itself was wrong.  So I
changed the assembly to Armv1.  Given the changes to objdump when
"disassembling all" it seemed like a good idea to force the disassembly to
'armv2' instead and actually accept the disassembly of the 26-bit Architecture
variants of tst, teq, cmn and cmp.

gas/ChangeLog

2018-10-31  Andre Vieira  <andre.simoesdiasvieira@arm.com>

	* testsuite/gas/arm/armv1.d: Assemble for Armv1 and disassemble for
	Armv2.