omap2/3: Fix DEBUG_LL for omap zoom2/3

Zoom2 and 3 have UARTs only on the external debug board.
GPMC needs to be mapped early to use it for DEBUG_LL.

Additionally, 0xfb000000 overlaps with other areas, so
use 0xfa400000 for the virtual address instead.

Note that with the pending serial.c patches you need to
set console=ttyS0,115200n8 as it will be the only UART
mapped. To use DEBUG_LL, you need to pass also earlyprintk
in cmdline.

Cc: Allen Pais <allen.pais@ti.com>
Acked-by: Vikram Pandita <vikram.pandita@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/io.c

@@ -166,6 +166,15 @@ static struct map_desc omap34xx_io_desc[] __initdata = {
 		.length		= L4_EMU_34XX_SIZE,
 		.type		= MT_DEVICE
 	},
+#if defined(CONFIG_DEBUG_LL) &&							\
+	(defined(CONFIG_MACH_OMAP_ZOOM2) || defined(CONFIG_MACH_OMAP_ZOOM3))
+	{
+		.virtual	= ZOOM_UART_VIRT,
+		.pfn		= __phys_to_pfn(ZOOM_UART_BASE),
+		.length		= SZ_1M,
+		.type		= MT_DEVICE
+	},
+#endif
 };
 #endif
 #ifdef	CONFIG_ARCH_OMAP4