west: Fix --openocd-search argument
west: Fix --openocd-search argument

Running west flash with the --openocd-search arg will result in the
openocd command being run with a -s param added for every character in
the passed DIR.

Fix the argparser to append all openocd-search DIRs into a list, instead
of just passing a string to the subcommand.

Signed-off-by: Jeremy Bettis <4df7b5147fee087dca33c181f288ee7dbf56e022@google.com>

zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr