i2c: Fix docbook problem

Sometimes kernel-doc and xmlto conspire to create output that is invalid
and causes problems.  Until I know a real/better solution, change the
source code that causes this.

If anyone has better fixes or can just explain what is happening here,
that would be great.

xmlto: input does not validate (status 1)
mmotm-2008-0314-1449/Documentation/DocBook/kernel-api.xml:71468: parser error : Opening and ending tag mismatch: programlisting line 71464 and para
   </para><para>
          ^
mmotm-2008-0314-1449/Documentation/DocBook/kernel-api.xml:71480: parser error : Opening and ending tag mismatch: para line 71473 and programlisting
</programlisting></informalexample>
                 ^
make[1]: *** [Documentation/DocBook/kernel-api.html] Error 1

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>