tests: work: exclude hifive1 board
tests: work: exclude hifive1 board

Exclude hifive1 board from tests/kernel/workq/work/kernel.work,
this board has a issue with this test suite and block all related
CI.

Signed-off-by: Lixin Guo <8de84fecf2daa12e9dd27dd0d7f47ee7775a73c0@intel.com>

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