dts: riscv: telink_b91: transform labels to uppercase
dts: riscv: telink_b91: transform labels to uppercase

Transformed all dts labels to uppercase.

Signed-off-by: Yuriy Vynnychek <a84feaeb1f754105d62c9a6971fe842c95d6cc94@telink-semi.com>

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