obexd: Add support for reinitializing a tty based server
obexd: Add support for reinitializing a tty based server

This patch adds support for retrying to open a tty when the daemon
receives a SIGUSR1 signal. This is e.g. needed for USB Gadget Serial so
that obexd can be notified that USB cable is plugged in and that a
matching device node is available.

ComputeCycles/bluez,pkarasev3/bluez,ComputeCycles/bluez,mapfau/bluez,pkarasev3/bluez,mapfau/bluez,ComputeCycles/bluez,ComputeCycles/bluez,pkarasev3/bluez,silent-snowman/bluez,mapfau/bluez,pstglia/external-bluetooth-bluez,mapfau/bluez,pkarasev3/bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez