setup-disk: don't add syslinux package for mounted root install unless requested

Closes #10455

See merge request !5

fixes #10456

fixes #10446

This allows running update-kernel on new alpine and to create
images from stable branch by overriding repository files.

Fixes: 3fd2ce43 "update-kernel: fix dtbs dir"

vecho should return success even if $VERBOSE is empty. Similar, qecho
should return success even if $QUIET is empty.

fixes !4

fixes #10451

rely on patch in for grub-mkconfig that will parse /etc/os-release

use '1', which should be dl-cdn, as the default answer

allow user set rootfs size via ROOT_SIZE. For lvm it will be passed
directly to lvmcreate. For the sfdisk partitions it will be a number in
MiB.

save exit state before cleaning up tempdir so we get the correct exit
code.

This fixes the problem where lbu exit with success on errors where disk
is full or similar.

Some drivers reference only the .bin but require additional
files such as .$board.txt or .clm_blob. Include all files
in modloop that might match. ref #9549

we need time to be correct for https certificates when setting up
apkrepos, so we call setup-ntp before setup-apkrepos.

ref #9911

modloopfw will add additional firmware to the modloop image
to work around not beeing detected by modinfo.

the setup-udev script is provided by eudev

prevent to exit with error due to set -e, if last firmware does not have
a *.txt file.

When -q option is specified:
- skip set root password
- auto configure network (dhcp)

this option will configure dhcp on first interface found which is "up"

remove variable that is not needed