scripts: twister: only load connected hardwares.
scripts: twister: only load connected hardwares.

only load hardwares with connected is true in
hardware map files.

Signed-off-by: Chen Peng1 <a9104ed43ee1e05962395401b47b879b137cfacf@intel.com>

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