doc: update list of transient units

Doing this manually seem to work only so well, but it is indeed hard to generate
automatically. Let's add the stuff that is missing for now.

AddRef= is not a unit file setting, remove it from the list.

docs/TRANSIENT-SETTINGS.md

@@ -5,9 +5,9 @@ title: What settings are currently available for transient units?
 # What settings are currently available for transient units?
 
 Our intention is to make all settings that are available as unit file settings
-also available for transient units, through the D-Bus API. At the moment, some
-unit types (device, swap, target) are not supported at all via unit types,
-but most others are pretty well supported, with some notable omissions.
+also available for transient units, through the D-Bus API. At the moment,
+device, swap, and target units are not supported at all as transient units, but
+others are pretty well supported.
 
 The lists below contain all settings currently available in unit files. The
 ones currently available in transient units are prefixed with `✓`.
@@ -51,7 +51,6 @@ Most generic unit settings are available for transient units.
 ✓ SuccessAction=
 ✓ FailureActionExitStatus=
 ✓ SuccessActionExitStatus=
-✓ AddRef=
 ✓ RebootArgument=
 ✓ ConditionPathExists=
 ✓ ConditionPathExistsGlob=
@@ -185,6 +184,7 @@ All execution-related settings are available for transient units.
 ✓ PrivateMounts=
 ✓ ProtectKernelTunables=
 ✓ ProtectKernelModules=
+✓ ProtectKernelLogs=
 ✓ ProtectControlGroups=
 ✓ PrivateNetwork=
 ✓ PrivateUsers=
@@ -271,6 +271,7 @@ All process killing settings are available for transient units:
 ✓ SendSIGHUP=
 ✓ KillMode=
 ✓ KillSignal=
+✓ RestartKillSignal=
 ✓ FinalKillSignal=
 ✓ WatchdogSignal=
 ```
@@ -310,6 +311,7 @@ Most service unit settings are available for transient units.
   Sockets=
 ✓ USBFunctionDescriptors=
 ✓ USBFunctionStrings=
+✓ OOMPolicy=
 ```
 
 ## Mount Unit Settings