soc: ixp4xx: Protect IXP4xx SoC drivers by ARCH_IXP4XX || COMPILE_TEST

The move of the IXP4xx SoC drivers exposed their config options on all
platforms.

Fix this by wrapping them inside an ARCH_IXP4XX or COMPILE_TEST block.

Link: https://lore.kernel.org/r/[email protected]
Fixes: fcf2d8978c ("ARM: ixp4xx: Move NPE and QMGR to drivers/soc")
Signed-off-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Linus Walleij <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>

drivers/soc/ixp4xx/Kconfig

@@ -1,4 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0-only
+if ARCH_IXP4XX || COMPILE_TEST
+
 menu "IXP4xx SoC drivers"
 
 config IXP4XX_QMGR
@@ -15,3 +17,5 @@ config IXP4XX_NPE
 	  and is automatically selected by Ethernet and HSS drivers.
 
 endmenu
+
+endif