soc: nordic: nrf54h20: Make HSFLL trims optional

If no HSFLL needs trimming, then `trim_hsfll()` should be compiled out.
This makes it easier to reuse the rest of `soc.c` out of tree.

Furthermore, some HSFLL instances can be trimmed before booting Zephyr,
so the FICR client properties in the DT binding should not be required.

Signed-off-by: Grzegorz Swiderski <grzegorz.swiderski@nordicsemi.no>

dts/bindings/clock/nordic,nrf-hsfll.yaml

@@ -57,9 +57,3 @@ properties:
       - 368000000
       - 384000000
       - 400000000
-
-  nordic,ficrs:
-    required: true
-
-  nordic,ficr-names:
-    required: true

soc/nordic/nrf54h/soc.c

@@ -55,6 +55,8 @@ static void power_domain_init(void)
 
 static int trim_hsfll(void)
 {
+#if defined(HSFLL_NODE)
+
 	NRF_HSFLL_Type *hsfll = (NRF_HSFLL_Type *)DT_REG_ADDR(HSFLL_NODE);
 	nrf_hsfll_trim_t trim = {
 		.vsup = sys_read32(FICR_ADDR_GET(HSFLL_NODE, vsup)),
@@ -77,6 +79,8 @@ static int trim_hsfll(void)
 	LOG_DBG("NRF_HSFLL->TRIM.COARSE = %d", hsfll->TRIM.COARSE);
 	LOG_DBG("NRF_HSFLL->TRIM.FINE = %d", hsfll->TRIM.FINE);
 
+#endif /* defined(HSFLL_NODE) */
+
 	return 0;
 }