bc: eliminate struct BcInstPtr::results_len_before_call, it is redundant

function                                             old     new   delta
zbc_program_call                                     332     318     -14
zxc_program_exec                                    4147    4087     -60
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(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-74)             Total: -74 bytes

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