JackSettings: Raise extra latency limit to 99999

This was unset, giving it a max of 99

resources/ui/settings_jack.ui

@@ -1119,6 +1119,9 @@ Also known as buffer size</string>
             <property name="toolTip">
              <string>Extra input latency (frames)</string>
             </property>
+            <property name="maximum">
+             <number>99999</number>
+            </property>
            </widget>
           </item>
           <item row="1" column="0">
@@ -1145,6 +1148,9 @@ Also known as buffer size</string>
             <property name="toolTip">
              <string>Extra output latency (frames)</string>
             </property>
+            <property name="maximum">
+             <number>99999</number>
+            </property>
            </widget>
           </item>
          </layout>