allow for the omap4430 es2.3 revision to be recognized in the
omap4_check_revision() function.

most aspects of all omap4430 es2.x versions are identical, however
a number of small variations such as default pullup or pulldown
resistor configurations vary between revisions.

detailed information on silicon errata for omap4430 revisions can
be found at http://focus.ti.com/pdfs/wtbu/swpz009D.pdfSigned-off-by: NDavid Anders <x0132446@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>