udev: add option to trigger parent devices despite filters

This commit add the `-i` option to `udevadm trigger` that force it to
match parent devices even if they're excluded from filters.
The rationale is that some embedded devices have a huge number of
platform devices ( ~ 4k for MX8 ) they are there because they're defined
in the device tree but there isn't any action or udev rules associated
with them.

So at boot a significant time is spend triggering and processing rules
for devices that don't produce any effect and we would like to filter
them by calling:

```
udevadm trigger --type=device --action=add -s block -s tty
```

instead of the normal

```
udevadm trigger --type=device --action=add
```

so we can use filter to filter out only subsystems for we we know that
we have rules in place that do something useful.

On the other side action / rules are not triggered until the parent is
triggered ( which is part of another subsystem), so the additional option
will allows udev to complete the coldplug with only the devices we care.

Example on iMX8:

.Without the new option
```
root@dev:~# udevadm trigger --dry-run  -s block --action=add -v
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0boot0
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0boot1
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p1
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p2
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p3
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p4
```

.With the new option
```
root@dev:~# udevadm trigger --dry-run -i -s block --action=add -v
/sys/devices/platform
/sys/devices/platform/bus@5b000000
/sys/devices/platform/bus@5b000000/5b010000.mmc
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0boot0
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0boot1
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p1
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p2
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p3
/sys/devices/platform/bus@5b000000/5b010000.mmc/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p4
```
Boot time reduction with this is place is ~ 1 second.

shell-completion/bash/udevadm

@@ -58,7 +58,7 @@ _udevadm() {
                     --json --subsystem-match --subsystem-nomatch --attr-match --attr-nomatch --property-match
                     --tag-match --sysname-match --name-match --parent-match'
         [TRIGGER_STANDALONE]='-v --verbose -n --dry-run -q --quiet -w --settle --wait-daemon --uuid
-                              --initialized-match --initialized-nomatch'
+                              --initialized-match --initialized-nomatch --include-parents'
         [TRIGGER_ARG]='-t --type -c --action -s --subsystem-match -S --subsystem-nomatch
                        -a --attr-match -A --attr-nomatch -p --property-match
                        -g --tag-match -y --sysname-match --name-match -b --parent-match