ARM: fix single-step of Thumb unconditional branch

Only type 1 branch instruction has a condition code, not type 2.
Currently they're both tagged with ARM_B which doesn't allow for the
distinction.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

src/target/arm_simulator.c

@@ -317,8 +317,8 @@ int arm_simulate_step_core(target_t *target, uint32_t *dry_run_pc, struct arm_si
 			return retval;
 		instruction_size = 2;
 
-		/* check condition code (only for branch instructions) */
-		if (instruction.type == ARM_B &&
+		/* check condition code (only for branch (1) instructions) */
+		if ((opcode & 0xf000) == 0xd000 &&
 		    !thumb_pass_branch_condition(sim->get_cpsr(sim, 0, 32), opcode))
 		{
 			if (dry_run_pc)