Improve error message if database is missing

If the chip configs database is missing, the tool should
provide a hint on how to fix the issue.

Change-Id: Iefbb5ecec9511e76e5ef2b547f5788144370fd28
Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-on: https://review.coreboot.org/c/em100/+/38284
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/em100.c b/em100.c
index 46f2c64..2d51bc9 100644
--- a/em100.c
+++ b/em100.c
@@ -671,7 +671,8 @@
 	configs = tar_load_compressed(configs_name);
 	free(configs_name);
 	if (!configs) {
-		printf("Can't find chip configs in $EM100_HOME/configs.tar.xz.\n");
+		printf("Can't find chip configs in $EM100_HOME/configs.tar.xz.\n"
+				"Please run: em100 --update-files.\n");
 		return NULL;
 	}