env_sf: Fix recovery default

The u-boot environment is redundantly stored in a NOR flash on our boards.
Redundant means that there are two places to store the environment. But only
one of the two is active. I discovered that on one board the u-boot (env_sf)
uses the environment from the second place and the Kernel (fw_printenv) uses
the environment from the first place.
To decide which is the active environment there is a byte inside the
environment. 1 means active and 0 means obsolete. But on that board both
environments had have a 1. This can happen if a power loss or reset occurs
during writing the environment. In this situation the u-boot (env_sf)
implementation uses the second environment as default. But the Kernel
(fw_printenv) implementation uses the first environment as default.

This commit corrects the default in the u-boot env_sf implementation when a
problem was detected. Now the recovery default is the same like in all other
environment implementations. E.g. fw_printenv and env_flash. This ensures that
u-boot and Kernel use the same environment.

Signed-off-by: Mario Schuknecht <mario.schuknecht@dresearch-fe.de>
diff --git a/common/env_sf.c b/common/env_sf.c
index 5e3729c..e928f57 100644
--- a/common/env_sf.c
+++ b/common/env_sf.c
@@ -188,15 +188,17 @@
 		   tmp_env2->flags == ACTIVE_FLAG) {
 		gd->env_valid = 2;
 	} else if (tmp_env1->flags == tmp_env2->flags) {
-		gd->env_valid = 2;
+		gd->env_valid = 1;
 	} else if (tmp_env1->flags == 0xFF) {
+		gd->env_valid = 1;
+	} else if (tmp_env2->flags == 0xFF) {
 		gd->env_valid = 2;
 	} else {
 		/*
 		 * this differs from code in env_flash.c, but I think a sane
 		 * default path is desirable.
 		 */
-		gd->env_valid = 2;
+		gd->env_valid = 1;
 	}
 
 	if (gd->env_valid == 1)