Fix asn1_item_print_ctx

The call to asn1_do_adb can return NULL on error, so we should check the
return value before attempting to use it.

(Imported from upstream's 34a7ed0c39aa3ab67eea1e106577525eaf0d7a00.)

Change-Id: Ia43cdc73b5f1d16e6fc907b5aaf13c9df5a9958c
Reviewed-on: https://boringssl-review.googlesource.com/4007
Reviewed-by: Adam Langley <agl@google.com>
1 file changed