ata: pata_pxa: add compile test support

Add Kconfig dependendy on COMPILE_TEST to allow compile tests with
configs that do not enable ARCH_PXA.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index a07cbc4..be812fe 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -969,7 +969,7 @@
 
 config PATA_PXA
 	tristate "PXA DMA-capable PATA support"
-	depends on ARCH_PXA
+	depends on ARCH_PXA || COMPILE_TEST
 	help
 	  This option enables support for harddrive attached to PXA CPU's bus.