boot: Fix syntax in fdt_overlay_apply_verbose() error message

Remove superfluous "did".

Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
diff --git a/boot/fdt_support.c b/boot/fdt_support.c
index 5e49078..b15d077 100644
--- a/boot/fdt_support.c
+++ b/boot/fdt_support.c
@@ -2095,7 +2095,7 @@
 		printf("failed on fdt_overlay_apply(): %s\n",
 				fdt_strerror(err));
 		if (!has_symbols) {
-			printf("base fdt does did not have a /__symbols__ node\n");
+			printf("base fdt does not have a /__symbols__ node\n");
 			printf("make sure you've compiled with -@\n");
 		}
 	}