kconfig: Adjust ordering so that defaults work as expected

At present defaults in arch-specific Kconfig files are ignored if the
top-level item comes ahead of it in include order. This means that it is
not possible to have a U-Boot default that architectures and boards can
override. This does not seem very useful.

Move the include earlier to support this.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

Kconfig

@@ -12,6 +12,9 @@ config KCONFIG_OBJDIR
 	string
 	option env="KCONFIG_OBJDIR"
 
+# Allow defaults in arch-specific code to override any given here
+source "arch/Kconfig"
+
 menu "General setup"
 
 config LOCALVERSION
@@ -172,8 +175,6 @@ config SYS_CLK_FREQ
 
 endmenu		# Boot images
 
-source "arch/Kconfig"
-
 source "common/Kconfig"
 
 source "dts/Kconfig"