dsp5680xx - flash module clk to freescale cfg value

dsp5680xx - flash module clk to freescale cfg value

the flash module clock was set according to a spreadsheet from freescale, now it's set according to the configuration file used by the Freescale Flash Programmer.
both work, but i think it's better to use the one used by a software that's made by Freescale (should be correct...)

Change-Id: I382197a3eb43dd47ff4b9b83d5e05008d5613fc6
Signed-off-by: Rodrigo L. Rosa <rodrigorosa.lg@gmail.com>
Reviewed-on: http://openocd.zylin.com/223
Tested-by: jenkins
Reviewed-by: Øyvind Harboe <oyvindharboe@gmail.com>