[PATCH v2 08/41] disk: part_dos: Fix a NULL pointer error

[Simon Glass]

When ext is NULL we cannot dereference it. Update the code flow to avoid
this, so that layout_mbr_partitions() can be used with partition tables
that do not include an extended partition.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

(no changes since v1)

 disk/part_dos.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

Applied to u-boot-dm/next, thanks!