dirent is #define’d to mingw_dirent in compat/mingw.h, with the
result that
obj_pool_gen(dirent, struct repo_dirent, 4096)
creates functions with names like mingw_dirent_alloc and
references to dirent_alloc go unresolved. Rename the functions
to dent_* to avoid this problem.
Reported-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>