expo: Begin implementation of a text editor

It is useful to be able to edit text, e.g. to allow the user to edit the
environment or the command-line arguments for the OS.

Add the beginnings of an implementation. Future work is needed to finish
this: keypress handling and scrolling. For now it just displays the
text.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/boot/cedit.c b/boot/cedit.c
index 9153fe7..5481025 100644
--- a/boot/cedit.c
+++ b/boot/cedit.c
@@ -82,6 +82,7 @@
 		case SCENEOBJT_IMAGE:
 		case SCENEOBJT_TEXT:
 		case SCENEOBJT_BOX:
+		case SCENEOBJT_TEXTEDIT:
 			break;
 		case SCENEOBJT_MENU:
 			scene_obj_set_pos(scn, obj->id, 50, y);
@@ -383,6 +384,7 @@
 	case SCENEOBJT_IMAGE:
 	case SCENEOBJT_TEXT:
 	case SCENEOBJT_BOX:
+	case SCENEOBJT_TEXTEDIT:
 		break;
 	case SCENEOBJT_TEXTLINE: {
 		const struct scene_obj_textline *tline;
@@ -483,6 +485,7 @@
 	case SCENEOBJT_IMAGE:
 	case SCENEOBJT_TEXT:
 	case SCENEOBJT_BOX:
+	case SCENEOBJT_TEXTEDIT:
 		break;
 	case SCENEOBJT_TEXTLINE: {
 		const struct scene_obj_textline *tline;
@@ -555,6 +558,7 @@
 	case SCENEOBJT_IMAGE:
 	case SCENEOBJT_TEXT:
 	case SCENEOBJT_BOX:
+	case SCENEOBJT_TEXTEDIT:
 		break;
 	case SCENEOBJT_MENU:
 		menu = (struct scene_obj_menu *)obj;
@@ -639,6 +643,7 @@
 	case SCENEOBJT_IMAGE:
 	case SCENEOBJT_TEXT:
 	case SCENEOBJT_BOX:
+	case SCENEOBJT_TEXTEDIT:
 		break;
 	case SCENEOBJT_MENU:
 		menu = (struct scene_obj_menu *)obj;