ref-manual: Updated FAQ entry regarding Proxy for SOCKS

Fixes [YOCTO #8637]

Added an example to the section for https_proxy.

Also added a small example section for SOCKS proxy.

Reported-by: Liam R. Howlett <liam.howlett@windriver.com>
(From yocto-docs rev: e17510f1209660b934e27f52a3e5c01a1f213453)

Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/ref-manual/faq.xml

@@ -286,13 +286,22 @@
         </question>
         <answer>
             <para>
-                Most source fetching by the OpenEmbedded build system is done by <filename>wget</filename>
-                and you therefore need to specify the proxy settings in a
-                <filename>.wgetrc</filename> file in your home directory.
-                Here are some example settings:
+                Most source fetching by the OpenEmbedded build system is done
+                by <filename>wget</filename> and you therefore need to specify
+                the proxy settings in a <filename>.wgetrc</filename> file
+                in your home directory.
+                Following are some example settings for different proxy types:
                 <literallayout class='monospaced'>
-     http_proxy = http://proxy.yoyodyne.com:18023/
-     ftp_proxy = http://proxy.yoyodyne.com:18023/
+     Http/FTP proxy:
+        https_proxy = http://proxy.yoyodyne.com:18023/
+        http_proxy = http://proxy.yoyodyne.com:18023/
+        ftp_proxy = http://proxy.yoyodyne.com:18023/
+
+     socks proxy:
+        export SOCKS_SERVER=`<replaceable>server</replaceable>:<replaceable>port</replaceable>`
+        unset http_proxy
+        unset https_proxy
+        unset ftp_proxy
                 </literallayout>
                 The Yocto Project also includes a
                 <filename>site.conf.sample</filename> file that shows how to