jtag: always configure enabled tap parameter appropriately

jtag: always configure enabled tap parameter appropriately

Commit f701c0cb seems to have introduced a regression for non-JTAG
transports as the newly created "tap" (DAP actually) ended up being
disabled, thus resulting in total lack of functionality.

This was exposed by a debug log demonstrating ftdi SWD transport
connection to mdr32f9q2i, the target wasn't examined on init and
couldn't be reset.

Change-Id: If53cbe800d4adc177aa3ac3219860e7fa15b3e49
Reported-by: Хайруллин Эльдар <eldar.khayrullin@mail.ru>
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/2261
Tested-by: jenkins
Reviewed-by: Angus Gratton <gus@projectgus.com>
Reviewed-by: Nemui Trinomius <nemuisan_kawausogasuki@live.jp>
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>