Add the new tablet mode options to the workspace KCM docs

doc/kcontrol/workspaceoptions/index.docbook

@@ -13,9 +13,9 @@
 <!-- TRANS:ROLES_OF_TRANSLATORS -->
 </authorgroup>
 
-<date>2020-06-30</date>
+<date>2022-05-14</date>
 
-<releaseinfo>&plasma; 5.20</releaseinfo>
+<releaseinfo>&plasma; 5.25</releaseinfo>
 
 <keywordset>
 <keyword>System Settings</keyword>
@@ -91,6 +91,23 @@ operating systems.</para>
 </listitem>
 </varlistentry>
 
+<varlistentry>
+<term><menuchoice><guimenu>Tablet Mode</guimenu><guimenuitem>Automatically enable as needed/Never optimize for touch usage</guimenuitem></menuchoice></term>
+<listitem>
+<para>Tablet Mode will be automatically activated whenever the system detects a 
+touchscreen but no mouse or touchpad. For example: when a transformable 
+laptop's keyboard is flipped around or detached.</para>
+</listitem>
+</varlistentry>
+
+<varlistentry>
+<term><guimenuitem>Always optimize for touch usage (default)/Never optimize for touch usage</guimenuitem></term>
+<listitem>
+<para>In Tablet Mode, many elements of the user interface will become larger to 
+more easily accommodate touch interaction.</para>
+</listitem>
+</varlistentry>
+
 </variablelist>
 
 </article>