arch: arm: cleanup of soc flags in arch

What is changed?

Use CMSIS SystemCoreClock via a dedicated flag instead of using
soc flags.

Why do we need this change?

This change is part of cleaning soc specific code out of arch folder.

Signed-off-by: Sudan Landge <sudan.landge@arm.com>

arch/arm/core/cortex_m/timing.c

@@ -28,8 +28,7 @@
  */
 static inline uint64_t z_arm_dwt_freq_get(void)
 {
-#if defined(CONFIG_SOC_FAMILY_NORDIC_NRF) || \
-	defined(CONFIG_SOC_SERIES_IMXRT6XX)
+#if defined(CONFIG_CMSIS_CORE_HAS_SYSTEM_CORE_CLOCK)
 	/*
 	 * DWT frequency is taken directly from the
 	 * System Core clock (CPU) frequency, if the

modules/cmsis/Kconfig

@@ -28,4 +28,9 @@ config CMSIS_M_CHECK_DEVICE_DEFINES
 	help
 	  This options enables the validation of CMSIS configuration flags.
 
+config CMSIS_CORE_HAS_SYSTEM_CORE_CLOCK
+	bool
+	help
+	  Enable this option if CMSIS SystemCoreClock symbols is available.
+
 endif

soc/nordic/Kconfig

@@ -9,6 +9,7 @@
 config SOC_FAMILY_NORDIC_NRF
 	select SOC_COMPATIBLE_NRF
 	select SOC_RESET_HOOK if ARM
+	select CMSIS_CORE_HAS_SYSTEM_CORE_CLOCK if ARM
 
 if SOC_FAMILY_NORDIC_NRF
 

soc/nxp/imxrt/imxrt6xx/Kconfig.defconfig

@@ -5,6 +5,10 @@
 
 if SOC_SERIES_IMXRT6XX
 
+config CMSIS_CORE_HAS_SYSTEM_CORE_CLOCK
+	bool
+	default y
+
 # alias for hal
 config SOC_SERIES_IMX_RT6XX
 	bool