ata: ahci-imx: Fix MODULE_ALIAS

'ahci:' is an invalid prefix, preventing the module from autoloading.
Fix this by using the 'platform:' prefix and DRV_NAME.

Fixes: 9e54eae2 ("ahci_imx: add ahci sata support on imx platforms")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

drivers/ata/ahci_imx.c

@@ -1235,4 +1235,4 @@ module_platform_driver(imx_ahci_driver);
 MODULE_DESCRIPTION("Freescale i.MX AHCI SATA platform driver");
 MODULE_AUTHOR("Richard Zhu <Hong-Xing.Zhu@freescale.com>");
 MODULE_LICENSE("GPL");
-MODULE_ALIAS("ahci:imx");
+MODULE_ALIAS("platform:" DRV_NAME);