Change to use sfdisk

Use sfdisk instead of lsblk to get the partition table. This requires
some changes in how the size of partitions are checked since sfdisk
records disk size in sectors, not MiB.

tests/kola/disks/partition-scheme

@@ -11,10 +11,10 @@ set -xeuo pipefail
 
 root_part=$(findmnt -n -o SOURCE /sysroot)
 disk_name=$(lsblk --json -o PKNAME --path "$root_part" | jq --raw-output '.blockdevices[].pkname')
-diskData=$(lsblk --json --bytes -o NAME,FSTYPE,START,SIZE,MOUNTPOINT,PARTLABEL,PARTTYPENAME,LOG-SEC "$disk_name" | jq '.blockdevices[]' )
-partitionData=$(echo $diskData | jq '.children[]')
-totalPartitions=$(echo $diskData | jq '.children | length')
-sector_size=$(echo $diskData | jq '.["log-sec"]')
+diskData=$(sfdisk --json "$disk_name" | jq '.partitiontable' )
+partitionData=$(echo $diskData | jq '.partitions[]')
+totalPartitions=$(echo $diskData | jq '.partitions | length')
+sector_size=$(echo $diskData | jq .sectorsize)
 
 if [[ $totalPartitions -ne 4 ]]; then
     fatal "Expected 4 partitions, got $totalPartitions"
@@ -37,12 +37,12 @@ declare -A expected=(
 # There is a 1MiB gap at the beginning of the disks
 expected_start=$(( 1 * $ONE_MiB / $sector_size ))
 
-# Iterate over the partitions and check their 
+# Iterate over the partitions and check their start and size
 for key in ${!expected[@]}; do
-    echo "${key}, ${expected[${key}]}"
     size_MiB="${expected[${key}]}"
-    start=$(echo "$partitionData" | jq "select ( .partlabel == \"$key\") | .start")
-    size=$(echo "$partitionData" | jq "select ( .partlabel == \"$key\") | .size")
+    start=$(echo "$partitionData" | jq "select ( .name == \"$key\") | .start")
+    sectors=$(echo "$partitionData" | jq "select ( .name == \"$key\") | .size")
+    size=$(( $sectors * $sector_size ))
     if [[ "$start" -ne "$expected_start" ]]; then
         fatal "Expected $key partition start sector of $expected_start, got $start"
     fi