Typo fix

PR: docs/37789
Submitted by: Marc Fonvieille <marc@freebsd-fr.org>

en_US.ISO8859-1/books/handbook/install/chapter.sgml

@@ -1940,7 +1940,7 @@ Mounting root from ufs:/dev/md0c
 
       <para>After choosing to begin a standard installation in
 	<application>Sysinstall</application> you will be shown this
-	message.</para>
+	message:</para>
 
       <screen>                                 Message
  In the next menu, you will need to set up a DOS-style ("fdisk")
@@ -2320,7 +2320,7 @@ Mounting root from ufs:/dev/md0c
 
       <para>Having chosen your partition layout you can now create it using
 	<application>Sysinstall</application>.  You will see this
-	message.</para>
+	message:</para>
 
       <screen>                                 Message
  Now, you need to create BSD partitions inside of the fdisk