Remove the hacks needed to support ash and mksh concurrently.

We no longer have ash, and we'd rather not have unnecessary symbolic links
on the system.

Change-Id: Icfb1a51f1baaf1861c203f6ed93843b094deb65d
diff --git a/core/build-system.html b/core/build-system.html
index 760589a..397eef4 100644
--- a/core/build-system.html
+++ b/core/build-system.html
@@ -247,7 +247,6 @@
         for <code>eng</code>.
         <ul>
         <li>Installs modules tagged with: <code>eng</code>, <code>debug</code>,
-            <code>shell_</code>$(TARGET_SHELL),
             <code>user</code>, and/or <code>development</code>.
         <li>Installs non-APK modules that have no tags specified.
         <li>Installs APKs according to the product definition files, in
@@ -267,7 +266,7 @@
         <p>
         This is the flavor intended to be the final release bits.
         <ul>
-        <li>Installs modules tagged with <code>shell_</code>$(TARGET_SHELL) and <code>user</code>.
+        <li>Installs modules tagged with <code>user</code>.
         <li>Installs non-APK modules that have no tags specified.
         <li>Installs APKs according to the product definition files; tags
             are ignored for APK modules.
@@ -674,8 +673,7 @@
 <h4>LOCAL_MODULE_TAGS</h4>
 <p>Set <code>LOCAL_MODULE_TAGS</code> to any number of whitespace-separated
 tags.  If the tag list is empty or contains <code>droid</code>, the module
-will get installed as part of a <code>make droid</code>.  Modules with the tag
-<code>shell_</code>$(TARGET_SHELL) will also be installed. Otherwise, it will
+will get installed as part of a <code>make droid</code>.  Otherwise, it will
 only get installed by running <code>make &lt;your-module&gt;</code>
 or with the <code>make all</code> pseudotarget.</p>