Although "naive" counting function is not too slow and is smaller,
using it on e.g. each of 1024 words of CPU mask feels wrong.
function old new delta
bb_popcnt_32 - 52 +52
get_prefix 323 321 -2
nproc_main 206 199 -7
d4_run_script 739 731 -8
ipcalc_main 533 507 -26
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(add/remove: 2/0 grow/shrink: 0/4 up/down: 52/-43) Total: 9 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>