pcie-gadget-spear: Add "platform:" prefix for platform modalias

Since 43cc71ee (platform: prefix MODALIAS
with "platform:"), the platform modalias is prefixed with "platform:".
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Pratyush Anand <pratyush.anand@st.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/misc/spear13xx_pcie_gadget.c

@@ -903,6 +903,6 @@ static void __exit spear_pcie_gadget_exit(void)
 }
 module_exit(spear_pcie_gadget_exit);
 
-MODULE_ALIAS("pcie-gadget-spear");
+MODULE_ALIAS("platform:pcie-gadget-spear");
 MODULE_AUTHOR("Pratyush Anand");
 MODULE_LICENSE("GPL");