Use <code> instead of <pre> to improve formatting

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

docs/buildroot.html

@@ -187,8 +187,8 @@
     <p>You <b>should never</b> use <code>make -jN</code> with
     Buildroot: it does not support <i>top-level parallel
     make</i>. Instead, use the <code>BR2_JLEVEL</code> option to tell
-    Buildroot to run each package compilation with <pre>make
-    -jN</pre>.</p>
+    Buildroot to run each package compilation with <code>make
+    -jN</code>.</p>
 
     <p>This command will generally perform the following steps:</p>
     <ul>