[nrf fromlist] dts: common: nordic: Add clock for timer12x

Add clock source for timer120 and timer121 nodes

Upstream PR #: 82103

Signed-off-by: Krzysztof Chruściński <[email protected]>

Author: nordic-krch

dts/common/nordic/nrf54h20.dtsi

@@ -623,6 +623,7 @@
 				power-domains = <&gpd NRF_GPD_FAST_ACTIVE1>;
 				max-bit-width = <32>;
 				max-frequency = <DT_FREQ_M(320)>;
+				clocks = <&hsfll120>;
 				prescaler = <0>;
 			};
 
@@ -635,6 +636,7 @@
 				power-domains = <&gpd NRF_GPD_FAST_ACTIVE1>;
 				max-bit-width = <32>;
 				max-frequency = <DT_FREQ_M(320)>;
+				clocks = <&hsfll120>;
 				prescaler = <0>;
 			};