options: fix failure to parse trailing ',' in string list

A trailing separator in string list options was ignored after recent
commit e873d703e9 ("options: change option parsing to use bstr"),
which broke uses such as "-vo vdpau,". Fix.

1 files changed, 1 insertions, 2 deletions

diff --git a/bstr.c b/bstr.c
index a2a49cc371..219c136d7c 100644
--- a/bstr.c
+++ b/bstr.c
@@ -129,8 +129,7 @@ struct bstr bstr_splice(struct bstr str, int start, int end)
         end += str.len;
     end = FFMIN(end, str.len);
     start = FFMAX(start, 0);
-    if (start >= end)
-        return (struct bstr){NULL, 0};
+    end = FFMAX(end, start);
     str.start += start;
     str.len = end - start;
     return str;