adi_v5_jtag: implement DAP WAIT support

adi_v5_jtag: implement DAP WAIT support

ADIv5 specifies that DP and AP accesses may generate a WAIT
response when the hardware is not able to complete a request for various
reasons in time before the next request is sent. Currently, the software
treats a WAIT response as a fatal error and aborts operation on the DAP.

This patch implements WAIT handling by keeping a journal of all
outstanding and completed accesses, including their response status.
At certain times (when dap_run() is called), the journal is inspected
for WAIT responses and all discarded accesses are replayed to complete
them. Special care is taken to not re-execute already successfully
completed operations.

Change-Id: I2790070388cf1ab2e8c9a042d74eb3ef776aa583
Signed-off-by: Matthias Welwarsky <matthias@welwarsky.de>
Reviewed-on: http://openocd.zylin.com/3166
Tested-by: jenkins
Reviewed-by: Paul Fertser <fercerpav@gmail.com>