init: devices: Add option to accept any device as boot device

Targets like PCs/VMs usually don't have fixed boot devices.

For example, moving the disk to another controller would result
in getting different block device path.

To workaround this situation, add an option to bypass the boot
device filter, so that every block devices would get their
symlink in /dev/block/by-name/.

Usage: Specify `androidboot.boot_devices=any` on bootconfig or cmdline

Test: /dev/block/by-name/* exists when `androidboot.boot_devices=any`
Change-Id: I5ae0faf401dac71352dbb05115a2dd6f3e76adc2