boards, tests: nrf54h20: add nordic,clock-enable property

Applies to:

- UART/E (TXD)
- SPIM (SCK, MOSI)
- SPIS (SCK, MISO)
- TWIM (SDA, SCL)

Except fast-instances.

Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>