dev-manual: Updates to "Setting Up a Native Linux Host"

I made some terminology changes to be consistent with the
"build host" term.

(From yocto-docs rev: 8e00f6453cbc470c7572f2c18e23e44ce18a7336)

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

documentation/dev-manual/dev-manual-start.xml

@@ -464,8 +464,8 @@
                     </para></listitem>
                 <listitem><para>
                     <emphasis>Have Enough Free Memory:</emphasis>
-                    You should have at least 50 Gbytes of free disk space
-                    for building images.
+                    Your system should have at least 50 Gbytes of free disk
+                    space for building images.
                     </para></listitem>
                 <listitem><para>
                     <emphasis>Meet Minimal Version Requirements:</emphasis>
@@ -494,7 +494,7 @@
                 <listitem><para>
                     <emphasis>Install Development Host Packages:</emphasis>
                     Required development host packages vary depending on your
-                    build machine and what you want to do with the Yocto
+                    build host and what you want to do with the Yocto
                     Project.
                     Collectively, the number of required packages is large
                     if you want to be able to cover all cases.</para>