package linux-modules-5.4.0-72-generic 5.4.0-72.80~18.04.1 failed to install/upgrade: unable to make backup link of './boot/System.map-5.4.0-72-generic' before installing new version: Operation not permitted

At upgrading from Ubuntu 18.04 to 20.04 on an rk-3328-cc (Renegade) board it crashes.

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: linux-modules-5.4.0-72-generic 5.4.0-72.80~18.04.1
Uname: Linux 4.4.114 aarch64
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: arm64
CasperMD5CheckResult: skip
Date: Sun Apr 25 23:37:34 2021
Dependencies:

DuplicateSignature:
 package:linux-modules-5.4.0-72-generic:5.4.0-72.80~18.04.1
 Unpacking linux-modules-5.4.0-72-generic (5.4.0-72.80) over (5.4.0-72.80~18.04.1) ...
 dpkg: error processing archive /tmp/apt-dpkg-install-ZmQELF/0903-linux-modules-5.4.0-72-generic_5.4.0-72.80_arm64.deb (--unpack):
  unable to make backup link of './boot/System.map-5.4.0-72-generic' before installing new version: Operation not permitted
ErrorMessage: unable to make backup link of './boot/System.map-5.4.0-72-generic' before installing new version: Operation not permitted
Python3Details: /usr/bin/python3.8, Python 3.8.5, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.18, python-is-python2, 2.7.17-4
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.5
SourcePackage: linux-hwe-5.4
Title: package linux-modules-5.4.0-72-generic 5.4.0-72.80~18.04.1 failed to install/upgrade: unable to make backup link of './boot/System.map-5.4.0-72-generic' before installing new version: Operation not permitted
UpgradeStatus: Upgraded to focal on 2021-04-25 (0 days ago)