Reduce scope or eliminate temporary variables in jtag_add_statemove:

Reduce scope or eliminate temporary variables in jtag_add_statemove:
- Change types of tms_bits and tms_count to unsigned, eliminates a cast.
- Use moves[] only if needed; a single move can use goal_state directly.
- Declare loop induction variable inside its control statement.
- Remove retval in favor of direct returns.

git-svn-id: svn://svn.berlios.de/openocd/trunk@2137 b42882b7-edfa-0310-969c-e2dbd0fdcd60