busybox

bc: use smaller datatypes for limits, match GNU bc 'limits' output

function                                             old     new   delta
bc_vm_process                                        315     291     -24
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(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-24)             Total: -24 bytes
   text	   data	    bss	    dec	    hex	filename
 988303	    485	   7296	 996084	  f32f4	busybox_old
 988273	    485	   7296	 996054	  f32d6	busybox_unstripped

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