cpufreq: db8500: Fetch cpufreq table from platform data

By fetching the table as platform data we do not need the internally
hardcoded cpufreq table anymore.

Moreover the corresponding arm_opp idx2opp table, used for mapping
frequency to correct opp bits is also removed. This due to that the
opp bits is put directly in the index field of the cpufreq table.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>