Make sure to also update delta->nfiles when merging diffs
Make sure to also update delta->nfiles when merging diffs

When diffs are generated, the value for the 'nfiles' field of 'git_diff_delta'
will be consistent with the value in the 'status' field. Merging diffs can
modify the 'status' field of some deltas and the 'nfiles' field needs to be
updated accordingly.

jflesch/libgit2-mariadb,jflesch/libgit2-mariadb,jflesch/libgit2-mariadb,jflesch/libgit2-mariadb,jflesch/libgit2-mariadb,jflesch/libgit2-mariadb