Rename SPL_USB_HOST_SUPPORT to SPL_USB_HOST

Rename this option so that CONFIG_IS_ENABLED can be used with it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/usb/mtu3/mtu3_plat.c b/drivers/usb/mtu3/mtu3_plat.c
index b097471..b1b22b9 100644
--- a/drivers/usb/mtu3/mtu3_plat.c
+++ b/drivers/usb/mtu3/mtu3_plat.c
@@ -261,7 +261,7 @@
 };
 #endif
 
-#if defined(CONFIG_SPL_USB_HOST_SUPPORT) || \
+#if defined(CONFIG_SPL_USB_HOST) || \
 	(!defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_HOST))
 static int mtu3_host_probe(struct udevice *dev)
 {
@@ -329,7 +329,7 @@
 		break;
 #endif
 
-#if defined(CONFIG_SPL_USB_HOST_SUPPORT) || \
+#if defined(CONFIG_SPL_USB_HOST) || \
 	(!defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_HOST))
 	case USB_DR_MODE_HOST:
 		dev_dbg(parent, "%s: dr_mode: host\n", __func__);