ARM: tegra: Seaboard: enable multiple USB ports

The device tree already contains the required configuration for both the
USB1 and USB3 ports. Enable the required configuration options to enable
both these ports, which in turn allows the USB1 port to be used.

Note that on a true Seaboard, this port is typically used as a device
port hosting Tegra's USB recovery protocol. However, on the Springbank
derivative, this port is the only external USB port, so we enable it as
a host port so that USB peripherals may be used. Enabling this port in
U-Boot as a host port doesn't prevent the port from reverting to a
device port when the CPU is reset into recovery mode.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>

include/configs/seaboard.h

@@ -81,6 +81,7 @@
 #define CONFIG_SYS_MMC_ENV_PART 2
 
 /* USB Host support */
+#define CONFIG_USB_MAX_CONTROLLER_COUNT 3
 #define CONFIG_USB_EHCI
 #define CONFIG_USB_EHCI_TEGRA
 #define CONFIG_USB_STORAGE