libx265: Fix 'braces around scalar initializer' warning

x265 Reordered the x265_picture fields in the commit

https://github.com/videolan/x265/commit/51b1518de2414431f36eac592db15b667c25a7b9#diff-945b5354d8767dfac13334f2d22cf58fR107

Now the first field is an integer and not an array.
