inetd: use change_identity().

libbb: shrink our internal initgroups().
httpd: remove stray 'else' and 'index_page = "index.html"'

function                                             old     new   delta
httpd_main                                           750     743      -7
inetd_main                                          2033    2011     -22
bb_internal_initgroups                               251     228     -23
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-52)             Total: -52 bytes

1 files changed, 1 insertions, 1 deletions

diff --git a/libbb/change_identity.c b/libbb/change_identity.c
index f19aa8aaa..da840bfb3 100644
--- a/libbb/change_identity.c
+++ b/libbb/change_identity.c
@@ -35,7 +35,7 @@ void change_identity(const struct passwd *pw)
 {
         if (initgroups(pw->pw_name, pw->pw_gid) == -1)
                 bb_perror_msg_and_die("can't set groups");
-        endgrent(); /* ?? */
+        endgrent(); /* helps to close a fd used internally by libc */
         xsetgid(pw->pw_gid);
         xsetuid(pw->pw_uid);
 }