Convert CONFIG_ARCH_CPU_INIT to Kconfig

This converts the following to Kconfig:
   CONFIG_ARCH_CPU_INIT

Signed-off-by: Adam Ford <aford173@gmail.com>
Acked-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Felix Brack <fb@ltec.ch>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 12e9ea4..cbb2a2a 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -329,6 +329,12 @@
 	default 64 if SYS_CACHE_SHIFT_6
 	default 32 if SYS_CACHE_SHIFT_5
 
+config ARCH_CPU_INIT
+	bool "Enable ARCH_CPU_INIT"
+	help
+	  Some architectures require a call to arch_cpu_init()
+	  Say Y here to enable it
+
 config SYS_ARCH_TIMER
 	bool "ARM Generic Timer support"
 	depends on CPU_V7A || ARM64