pinctrl: intel: wrap Intel pin control drivers in an architecture check

The Intel pin control drivers are architecture specific so add an if arch
to check for X86 or compile test to ensure continued test coverage.

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>