Merge pull request #13246 from keszybz/add-SystemdOptions-efi-variable

Add efi variable to augment /proc/cmdline

diff --cc docs/ENVIRONMENT.md
Simple merge

diff --cc src/basic/cgroup-util.c
Simple merge

diff --cc src/basic/cgroup-util.h
Simple merge

diff --cc src/core/cgroup.c
Simple merge

diff --cc src/core/execute.c
Simple merge

diff --cc src/core/load-fragment.c
Simple merge

diff --cc src/core/mount-setup.c
Simple merge

diff --cc src/core/unit.c
Simple merge

diff --cc src/login/logind-dbus.c
Simple merge

diff --cc src/nspawn/nspawn.c
Simple merge

diff --cc src/shared/bootspec.c
Simple merge

diff --cc src/shared/bus-unit-util.c
Simple merge

diff --cc src/shared/unit-file.c
Simple merge