busybox

printf: fix printing +-prefixed numbers

Thanks to Cristian Ionescu-Idbohrn for noticing.

Also fix "%d" '  42' to skip leading whitespace.

function                                             old     new   delta
print_direc                                          435     454     +19
bb_strtoll                                            99     103      +4
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 23/0)               Total: 23 bytes

Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>