busybox

chrt: use correct min/max priorities

function                                             old     new   delta
chrt_main                                            369     432     +63
policies                                              48      96     +48
packed_usage                                       32239   32249     +10
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(add/remove: 0/0 grow/shrink: 3/0 up/down: 121/0)             Total: 121 bytes

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