init.d/agetty: set default respawn period to 60 seconds

Without a respawn period setting, the supervisor will give up on
respawning agetty after it is respawned respawn_max times. For most
daemons giving up like this is reasonable, but not for agettys. Agettys
should always be respawned unless they are respawning too fafst,.

If an agetty is respawning faster than 10 times in 60 seconds, this
seems to be too fast.

init.d/agetty.in

@@ -12,6 +12,7 @@
 description="start agetty on a terminal line"
 supervisor=supervise-daemon
 port="${RC_SVCNAME#*.}"
+respawn_period="${respawn_period:-60}"
 term_type="${term_type:-linux}"
 command=/sbin/agetty
 command_args_foreground="${agetty_options} ${port} ${baud} ${term_type}"