extendedcommands/nandroid: remove internal options if no sdcard and is_data_media

-force /data as backup_path if volume for /sdcard is null and the same is true

Change-Id: I927b723cde5b519d81402c6d841f2424627253e8

Conflicts:

	nandroid.c
diff --git a/nandroid.c b/nandroid.c
index 56c633d..ad44ae6 100644
--- a/nandroid.c
+++ b/nandroid.c
@@ -233,6 +233,12 @@
     }
     
     Volume* volume = volume_for_path(backup_path);
+    if (NULL == volume) {
+      if (strstr(backup_path, "/sdcard") == backup_path && is_data_media())
+          volume = volume_for_path("/data");
+      else
+          return print_and_error("Unable to find volume for backup path.\n");
+    }
     int ret;
     struct statfs s;
     if (NULL != volume) {