compile with _FILE_OFFSET_BITS=64

Build for p8.

New udev control logic imported from make-initrd scripts.
Udev-trigger replaced to udev-settle() in hardware wait loops.
All udev control code moved from init.c to new udev.c module.
Lazy initialization mode support added for work in cooperate
initrd: this is experimental future, turned off by
initrd-propagator.
disk.c, cdrom.c: 15 attempts with udev-settle() calls.
network.c: bridge up algorithm reviewed, fixed memory leaks.
network.c: 15 attempts to select and wait network interface;
probing.c, probing.h, dhcp.c: small fixes, now black list used.
modules_descr.h, stage1.c: deprecated header, unused code removed.
dhcp.c: fix potentially destructive typo (closes: #34322),
Workaround race conditions during disks detection (closes: #30315).
Workaround race conditions during bridging up network interfaces,
April/date.html
Multiple small code improvements, fixes for avoid memory leaks

Build for p8.

probing.c: added support for MMC devices when boot in LiveCD-mode
cdrom.c: fixed implicit declaration of function opendir warning
disk.c: Workaround race conditions during disks detection
cdrom.c, network.c, tools.c: Fix memory leaks.
tools.c: Don't do useless comparisons during cmdline processing.
Use ramdisk_size from kernel cmdline.
Check that RAM size is enough for ramdisk.

Fixed errors found by cppcheck.

probing.c: bump max disk number from 50 to 250 (closes: #32934)

disk.c: retry uuid/label based autodetection upon a pause

probing.c: load uas module too

use spawn to run udevadm (legion@; see also #32068)

modules.c: silence modprobe (some could be compiled in at times)

cdrom.c, disk.c: poke lazy udev to do its job while waiting for disk

cdrom.c: fix pointer arithmetics (ldv@)

cdrom.c: minor fixup for "1, 2, 1 seconds" visual effect
disk.c: slightly better "help me find my media" message
probing.c: ensure sd_mod along with usb_storage

ldv@'s workaround for media detection race condition (closes: #30315)