ata: fix Calxeda Highbank SATA driver dependencies

Make sata_highbank host driver depend on ARCH_HIGHBANK config option
as Calxeda Highbank SATA support is specific to Calxeda Highbank
SoCs and the driver to work requires suitable device tree node to
be defined.  Additionally allow the driver build if COMPILE_TEST
config option is set.

Cc: Mark Langsdorf <mark.langsdorf@calxeda.com>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index f4d9a6ab..23f15f48 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -272,6 +272,7 @@
 
 config SATA_HIGHBANK
 	tristate "Calxeda Highbank SATA support"
+	depends on ARCH_HIGHBANK || COMPILE_TEST
 	help
 	  This option enables support for the Calxeda Highbank SoC's
 	  onboard SATA.