Yet another fill-1 test fix

Yet another fill-1 test fix

tic4x fails due to being a 4 octets per byte target, while tic54x is 2
octets per byte.

mmix still fails with
fill-1.s:4: Error: unknown pseudo-op: `.l1:'
fill-1.s:6: Error: unknown pseudo-op: `.l2:'
fill-1.s:3: Error: .space specifies non-absolute value

and if the labels are changed to L1 and L2 then mep-elf fails with
fill-1.s:3: Error: .space specifies non-absolute value

Since both of those look like they ought to be investigated by the
target maintainers, I'm tweaking the test to fail on both targets.

	* testsuite/gas/all/fill-1.d: Exclude tic4x and tic54x.
	* testsuite/gas/all/fill-1.s: Use L1 rather than .L1.