hwrng: Add quality parameter to msm_rng driver

With the recent changes in upstream, certain parameters
are updated in the core random number generator driver.
So update HW rng driver to provide the quality estimation
of true entropy in RNG's bitstream. Value 700 corresponds
to 70% an arbitrary value, which is taken from 3.10.

Change-Id: Ia6cffa568b1e3f1e034b998de0fad2f0b12e10fa
Signed-off-by: AnilKumar Chimata <anilc@codeaurora.org>
Signed-off-by: Zhen Kong <zkong@codeaurora.org>