docs: update install docs for meson

Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>

docs/install.html

@@ -43,12 +43,11 @@
 <li><a href="http://www.scons.org/">SCons</a> is required for building on
 Windows and optional for Linux (it's an alternative to meson.)
 </li>
-<li>Android Build system when building as native Android component. Autoconf
+<li>Android Build system when building as native Android component. Meson
 is used when when building ARC.
 </li>
 </ul>
 
-
 <h4>Compiler</h4>
 <p>
 The following compilers are known to work, if you know of others or you're
@@ -63,12 +62,6 @@ willing to maintain support for other compiler get in touch.
 
 
 <h4>Third party/extra tools.</h4>
-<p>
-<strong>Note</strong>: These should not be required, when building from a release tarball. If
-you think you've spotted a bug let developers know by filing a
-<a href="bugs.html">bug report</a>.
-</p>
-
 
 <ul>
 <li><a href="https://www.python.org/">Python</a> - Python is required.
@@ -114,9 +107,12 @@ the packaging tool used by your distro.
 
 <h2 id="meson">2. Building with meson</h2>
 
+<p><string>Meson &6t;= 0.46.0 is required</string></p>
+
 <p>
 Meson is the latest build system in mesa, it is currently able to build for
-*nix systems like Linux and BSD, and will be able to build for windows as well.
+*nix systems like Linux and BSD, macOS, Haiku, and will be able to build for
+windows as well.
 </p>
 
 <p>