bc: code shrink - convert two macros to functions

bc: code shrink - convert two macros to functions

function                                             old     new   delta
bc_program_printStream                                 -     185    +185
bc_program_pushArray                                   -     147    +147
bc_program_exec                                     4132    4219     +87
bc_vec_pop                                             -      27     +27
bc_vec_top                                             -      13     +13
bc_num_ulong                                          92     103     +11
bc_vm_run                                           1905    1903      -2
bc_vm_process                                         94      92      -2
bc_program_reset                                      72      70      -2
bc_program_prep                                       93      91      -2
bc_program_call                                      366     364      -2
bc_parse_startBody                                    47      45      -2
bc_parse_parse                                       464     462      -2
bc_parse_else                                        137     135      -2
bc_parse_body                                        118     116      -2
bc_program_num                                      1129    1125      -4
bc_parse_text                                        147     143      -4
bc_program_retire                                     40      35      -5
bc_program_print                                     778     773      -5
bc_program_modexp                                    746     741      -5
bc_program_pushVar                                   215     208      -7
bc_program_copyToVar                                 323     316      -7
bc_parse_operator                                    184     177      -7
bc_parse_noElse                                       65      56      -9
bc_program_binOpRetire                                56      46     -10
bc_parse_stmt                                       2271    2261     -10
bc_program_execStr                                   543     528     -15
bc_program_assignStr                                 161     146     -15
bc_parse_expr_empty_ok                              2178    2157     -21
bc_parse_endBody                                     420     375     -45
bc_program_asciify                                   464       -    -464
------------------------------------------------------------------------------
(add/remove: 4/1 grow/shrink: 2/24 up/down: 470/-651)        Total: -181 bytes
   text	   data	    bss	    dec	    hex	filename
 987227	    485	   7296	 995008	  f2ec0	busybox_old
 987046	    485	   7296	 994827	  f2e0b	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>