tests: drivers: hwinfo: Cleanup testcase.yaml
tests: drivers: hwinfo: Cleanup testcase.yaml

The testcase.yaml had multiple tests defined but they didn't do anything
different.  Remove the duplication and rename to drivers.hwinfo.api.

Signed-off-by: Kumar Gala <a5e5248af4cd4f0ed8c515f61d40a6e2db46a66e@linaro.org>

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