ARM: dts: msm: update devfreq node frequency mapping in sdm670

sdm670 target got update on the cpu core frequency plan
update devfreq node mappings with the updated frequency
plan.

Change-Id: Ic9067b5ce87f11ab5b1fd690c094e2dbda98975d
Signed-off-by: Santosh Mardi <gsantosh@codeaurora.org>