jtag/jlink: switch to command 'adapter serial'

jtag/jlink: switch to command 'adapter serial'

The driver jlink defines the command 'jlink serial' to specify the
serial string of the adapter.

Remove and deprecate the driver command, and use 'adapter serial'.

Note: in former code the commands 'jlink serial' and 'jlink usb'
were mutually exclusive; running one of them would invalidate the
effect of a previous execution of the other. The new code gives
priority to 'adapter serial', even if executed before 'jlink usb'.

Change-Id: I920b0c136716f459b6fd6f7da8a01a7fa1ed389f
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/6656
Reviewed-by: zapb <dev@zapb.de>
Tested-by: jenkins