rework long option handling. saves ~1.2k

rework long option handling. saves ~1.2k

function                                             old     new   delta
tar_longopts                                           -     222    +222
static.udhcpc_longopts                                 -     192    +192
start_stop_daemon_longopts                             -     150    +150
getopt32                                            1045    1185    +140
static.wget_longopts                                   -     111    +111
static.od_longopts                                     -     105    +105
getopt_longopts                                        -      96     +96
install_longopts                                       -      67     +67
ipcalc_longopts                                        -      63     +63
static.hwclock_longopts                                -      54     +54
ftpgetput_longopts                                     -      52     +52
static.dumpleases_longopts                             -      32     +32
env_longopts                                           -      31     +31
runparts_longopts                                      -      30     +30
mv_longopts                                            -      24     +24
mkdir_longopts                                         -      19     +19
find_pair                                            164     180     +16
bb_null_long_options                                   -      16     +16
setconsole_longopts                                    -      10     +10
display_speed                                         91      98      +7
collect_blk                                          467     474      +7
show_color                                             4       1      -3
ls_main                                              913     904      -9
bb_default_long_options                               16       -     -16
ls_color_opt                                          32      10     -22
setconsole_long_options                               32       -     -32
arith                                               2077    2030     -47
mv_long_options                                       48       -     -48
mkdir_long_options                                    48       -     -48
env_long_options                                      48       -     -48
static.options                                       248     184     -64
runparts_long_options                                 80       -     -80
ftpgetput_long_options                                96       -     -96
static.hwclock_long_options                          112       -    -112
install_long_options                                 112       -    -112
static.long_options                                  144       -    -144
static.wget_long_options                             160       -    -160
longopts                                             160       -    -160
static.arg_options                                   304       -    -304
tar_long_options                                     320       -    -320
long_options                                         384       -    -384
------------------------------------------------------------------------------
(add/remove: 17/15 grow/shrink: 4/5 up/down: 1444/-2209)     Total: -765 bytes
   text    data     bss     dec     hex filename
 782618    1328   11900  795846   c24c6 busybox_old
 781354    1328   11900  794582   c1fd6 busybox_unstripped