When a user asks for blaster I, he or she should either get it, or get
an error, not blaster II driver.
Change-Id: Ibc7683676ce42773e2b14ea5ccb3d119d1e6acea
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/4381
Tested-by: jenkins