target: drop deprecated code for mem2array and array2mem

target: drop deprecated code for mem2array and array2mem

Commit e370e06b724f ("target: Deprecate 'array2mem' and
'mem2array''") has already replaced the deprecated root versions
of commands mem2array and array2mem with TCL proc's that use
'read_memory' and 'write_memory'. It has left the deprecated code
of the target's version of the commands because the effort to code
the TCL replacement was not considered valuable.

To drop the last jim_handler commands, I consider much easier and
less error-prone to code them in TCL instead of converting the
deprecated code to COMMAND_HANDLER.

Drop the code in target.c and extend the TCL proc's.
While there, add the TCL procs to _telnet_autocomplete_skip.

Change-Id: I97d2370d8af479434ddf5af68541f90913982bc0
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/8052
Tested-by: jenkins