16550: Use generic console_t data structure

Since now the generic console_t structure holds the UART base address as
well, let's use that generic location and drop the UART driver specific
data structure at all.

Change-Id: I5c2fe3b6a667acf80c808cfec4a64059a2c9c25f
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/plat/mediatek/mt8173/bl31_plat_setup.c b/plat/mediatek/mt8173/bl31_plat_setup.c
index 73a479b..bd7d0b0 100644
--- a/plat/mediatek/mt8173/bl31_plat_setup.c
+++ b/plat/mediatek/mt8173/bl31_plat_setup.c
@@ -100,7 +100,7 @@
 void bl31_early_platform_setup2(u_register_t arg0, u_register_t arg1,
 				u_register_t arg2, u_register_t arg3)
 {
-	static console_16550_t console;
+	static console_t console;
 
 	console_16550_register(MT8173_UART0_BASE, MT8173_UART_CLOCK, MT8173_BAUDRATE, &console);