hmp: Add help information for watchdog action: inject-nmi

virsh qemu-monitor-command --hmp help information of
watchdog_action missing inject-nmi which already supported
in Commit 795dc6e4

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2247
Signed-off-by: Dayu Liu <liu.dayu@zte.com.cn>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
[Mjt: decode and word-wrap commit message and add Resolves: tag]
1 file changed