fw_env: Fix double free

addr0 is being freed twice, leading to segmentation fault

Signed-off-by: Björn Stenberg <bjorn@haxx.se>
diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
index a5d7595..1ed0f7e 100644
--- a/tools/env/fw_env.c
+++ b/tools/env/fw_env.c
@@ -1566,7 +1566,7 @@
 		free(addr0);
 
 	if (addr1)
-		free(addr0);
+		free(addr1);
 
 	return ret;
 }