watchdog: allow millisecond spec (-t 250ms)

function                                             old     new   delta
packed_usage                                       23069   23113     +44
static.suffixes                                        -      24     +24
watchdog_main                                        147     160     +13
static.V                                               -       1      +1
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(add/remove: 2/0 grow/shrink: 2/0 up/down: 82/0)               Total: 82 bytes


2 files changed