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

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/20190823090352.12243-1-linus.walleij@linaro.org
Fixes: 6fbfb2b4a5418b0f ("ARM: ixp4xx: Move NPE and QMGR to drivers/soc")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>