tests: drivers: timer: Update GRTC LFRC based timer test

- add cpurad support
- adapt tolerances (were too tight)

Signed-off-by: Bartosz Miller <[email protected]>

Author: nordic-bami

tests/drivers/timer/grtc_timer_lfrc/boards/nrf54h20dk_nrf54h20_cpurad.overlay

@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: LicenseRef-Nordic-5-Clause */
+
+/ {
+	aliases {
+		tst-timer = &timer020;
+	};
+};
+
+&grtc {
+	/delete-property/ child-owned-channels;
+};
+
+&timer020 {
+	status = "okay";
+};

tests/drivers/timer/grtc_timer_lfrc/prj.conf

@@ -1,7 +1,6 @@
-CONFIG_ZTEST=y
 CONFIG_NRF_GRTC_TIMER=y
 CONFIG_CLOCK_CONTROL=y
 CONFIG_COUNTER=y
 
-CONFIG_LOG=y
-CONFIG_CLOCK_CONTROL_LOG_LEVEL_DBG=y
+CONFIG_LOG=n
+CONFIG_PRINTK=y