ahci: st: Only build for ST-Micro h/w

This device is designed specifically to run on ST-Microelectronics'
hardware. To ensure no attempts are made to run on anything incompatible
we add a dependency on ST architecture
Suggested-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

drivers/ata/Kconfig

@@ -100,6 +100,7 @@ config SATA_AHCI_PLATFORM
 config AHCI_ST
 	tristate "ST AHCI SATA support"
 	depends on SATA_AHCI_PLATFORM
+	depends on ARCH_STI
 	help
 	  This option enables support for ST AHCI SATA controller.