UBI: do not print message about corruptes PEBs if we have none of them

Currently UBI prints

UBI: corrupted PEBs will be formatted

even if there are not corrupted PEBs. Fix this.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c
index a86c048..372a15a 100644
--- a/drivers/mtd/ubi/scan.c
+++ b/drivers/mtd/ubi/scan.c
@@ -964,7 +964,7 @@
 		}
 	}
 
-	if (si->corr_peb_count >= 0)
+	if (si->corr_peb_count > 0)
 		ubi_msg("corrupted PEBs will be formatted");
 	return 0;
 }