Implement a minimalist queue for DP/AP commands and reorganize the
code to use it.
There is no performance improvement; the queue elements are still
sent one-by-one on USB or on TCP during dap_run().
Change-Id: I8353563e59f883624bcc0fbe8b54955e4f27ccfa
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/6601
Tested-by: jenkins
Reviewed-by: Tarek BOCHKATI <tarek.bouchkati@gmail.com>