sunxi: kconfig: Add top-level ARCH_SUNXI

And make TARGET_SUN[45678]I a choice variable under this.

configs updated with:
    sed -i -e 's/^\(\+S:\)\?CONFIG_TARGET_SUN.I=y/\1CONFIG_ARCH_SUNXI=y\n&/g' configs/*

Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 43700c3..bd774d4 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -663,30 +663,8 @@
 	select CPU_V7
 	select SUPPORT_SPL
 
-config TARGET_SUN4I
-	bool "Support sun4i"
-	select CPU_V7
-	select SUPPORT_SPL
-
-config TARGET_SUN5I
-	bool "Support sun5i"
-	select CPU_V7
-	select SUPPORT_SPL
-
-config TARGET_SUN6I
-	bool "Support sun6i"
-	select CPU_V7
-	select SUPPORT_SPL
-
-config TARGET_SUN7I
-	bool "Support sun7i"
-	select CPU_V7
-	select SUPPORT_SPL
-
-config TARGET_SUN8I
-	bool "Support sun8i"
-	select CPU_V7
-	select SUPPORT_SPL
+config ARCH_SUNXI
+	bool "Support sunxi (Allwinner) SoCs"
 
 config TARGET_SNOWBALL
 	bool "Support snowball"