OMAP3 SDRC: Drop 133.3MHz, 66.6MHz rates from Micron SDRAM params file

Boards that used 133.3MHz maximum rate SDRAM were never released to the
public and presumably used the OMAPZoom kernel; so, drop these unused
rates.  Viz.:

    http://marc.info/?l=linux-omap&m=124232922426311&w=2

This patch is a collaboration between Richard Woodruff <r-woodruff2@ti.com>,
Tony Lindgren <tony@atomide.com>, and Paul Walmsley <paul@pwsan.com>.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>