tar2vm: reworked to use sfdisk

The issue (#28002) resulting in vm image build error reading

  Syntax error at or above line 5 in file '/etc/lilo-loop.conf'

was caused by fdisk-2.22 changing its "-l" option output format
to drop the very mention of the long irrelevant crap named "CHS".

The problem is, however, that we still need that crap to piggyback
a loop device's fake geometry to lilo while installing it there.

Reported by icesik@.

.gear/mkimage-profiles.spec

@@ -15,10 +15,10 @@ BuildRequires: rsync asciidoc-a2x xmlgraphics-fop fonts-ttf-dejavu
 BuildRequires: /proc
 
 Requires: rsync git-core
-Requires: time schedutils
+Requires: time schedutils sfdisk
 Requires: mkimage >= 0.2.0
 
-# Recommends: graphviz
+# Recommends: graphviz qemu-img
 
 %define mpdir %_datadir/%name
 %add_findreq_skiplist %mpdir/*.in/*

bin/tar2vm

@@ -42,7 +42,7 @@ ROOTFSTYPE="${4:-ext4}"
 ROOTDEV="/dev/sda1"
 
 # last preparations...
-for i in losetup parted kpartx mkfs."$ROOTFSTYPE"; do
+for i in losetup sfdisk parted kpartx mkfs."$ROOTFSTYPE"; do
 	if ! type -t "$i" >&/dev/null; then
 		fatal "$i required but not found"
 	fi
@@ -98,8 +98,8 @@ chroot "$ROOTFS" make-initrd -k "$KERNEL"
 sed -i "s,$LOOPDEV1,$ROOTDEV," "$ROOTFS/etc/fstab"
 
 # configure and install bootloader
-REGEXP='^([0-9]+) heads, ([0-9]+) sectors/track, ([0-9]+) cylinders.*$'
-set -- $(fdisk -l "$LOOPDEV" | grep -E "$REGEXP" | sed -r "s@$REGEXP@\1 \2 \3@")
+REGEXP='^Disk .*: ([0-9]+) cylinders, ([0-9]+) heads, ([0-9]+) sectors/track*$'
+set -- $(sfdisk -l "$LOOPDEV" | grep -E "$REGEXP" | sed -r "s@$REGEXP@\1 \2 \3@")
 
 LILO_COMMON="lba32
 delay=1
@@ -113,9 +113,9 @@ cat > "$ROOTFS"/etc/lilo-loop.conf << EOF
 boot=$LOOPDEV
 disk=$LOOPDEV
   bios=0x80
-  heads=$1
-  sectors=$2
-  cylinders=$3
+  cylinders=$1
+  heads=$2
+  sectors=$3
   partition=$LOOPDEV1
   start=63
 $LILO_COMMON