Bug 21260: Indentation at higher levels for Availability/Location

Only whitespace changes and few comments.

Test plan:
Nothing to test. Count the spaces ;)

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: ava li <rubyli208@gmail.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>

koha-tmpl/opac-tmpl/bootstrap/en/xslt/MARC21slim2OPACResults.xsl

@@ -1244,6 +1244,8 @@
                             </xsl:for-each>
                             </span>
                         </xsl:if>
+
+        <!-- Availability line -->
         <span class="results_summary availability">
             <span class="label">Availability: </span>
             <xsl:choose>
@@ -1332,7 +1334,6 @@
                         </xsl:choose>
                     </xsl:otherwise>
                 </xsl:choose>
-
                 </span>
                 </xsl:when>
             </xsl:choose>
@@ -1453,6 +1454,9 @@
                        <xsl:text>). </xsl:text>                   </span>
             </xsl:if>
         </span>
+        <!-- End of Availability line -->
+
+        <!-- Location line -->
         <xsl:choose>
             <xsl:when test="($OPACItemLocation='location' or $OPACItemLocation='ccode') and (count(key('item-by-status', 'available'))!=0 or count(key('item-by-status', 'reference'))!=0)">
                 <span class="results_summary location">
@@ -1507,6 +1511,8 @@
                 </span>
             </xsl:when>
         </xsl:choose>
+        <!-- End of Location line -->
+
     </xsl:template>
 
     <xsl:template name="nameABCQ">