Update platform-backup to use 30GB partition

In order to support local installation, the platform-backup partition
needs to be large enough to support the install files.

The new recommended size is 30GB based on the following criteria:
ISO image (2.5GB)
5 patches (2.5GB) - 500M per patch
Compressed image archive (5G) - archive is currently 14G uncompressed
Platform Backup (10G) - current size

This change also includes an option to pass the partition size in the
boot parameters.

Test Plan:
AIO install with 240GB disk
AIO install with 500GB disk
AIO install with custom partition size
AIO install with smaller custom partition size
Standard install

AIO-DX upgrade from 21.05

Story: 2008966
Task: 43981
Depends-On: https://review.opendev.org/c/starlingx/config/+/817967
Signed-off-by: David Sullivan <david.sullivan@windriver.com>
Change-Id: Ie8c6def2382dad38371dd280fa304ebbc839b675

bsp-files/kickstarts/pre_disk_aio.cfg

@@ -82,10 +82,11 @@
 ROOTFS_SIZE=20000
 LOG_VOL_SIZE=8000
 SCRATCH_VOL_SIZE=16000
-PLATFORM_BACKUP_SIZE=10000
 BOOT_SIZE=500
 EFI_SIZE=300
 
+PLATFORM_BACKUP_SIZE=$persistent_size
+
 # The default disk size thresholds must align with the ones in
 #   config/.../sysinv/common/constants.py
 #   which are DEFAULT_SMALL_DISK_SIZE

bsp-files/kickstarts/pre_disk_controller.cfg

@@ -5,10 +5,11 @@
 ROOTFS_SIZE=20000
 LOG_VOL_SIZE=8000
 SCRATCH_VOL_SIZE=16000
-PLATFORM_BACKUP_SIZE=10000
 BOOT_SIZE=500
 EFI_SIZE=300
 
+PLATFORM_BACKUP_SIZE=$persistent_size
+
 ROOTFS_OPTIONS="defaults"
 profile_mode=`cat /proc/cmdline |xargs -n1 echo |grep security_profile= | grep extended`
 if [ -n "$profile_mode" ]; then

bsp-files/kickstarts/pre_disk_setup_common.cfg

@@ -22,6 +22,10 @@ fi
 if [ -z "$rootfs_device" ]; then
     rootfs_device=$(get_disk_dev)
 fi
+if [ -z "$persistent_size" ]; then
+    # Default backup partition size in MiB
+    persistent_size=30000
+fi
 
 # Get root and boot devices
 orig_rootfs_device=$rootfs_device