msm: clock-8960/8660: Support 32/64MHz prng clock frequency plan

Add support for both the 32MHz and the 64MHz prng frequencies.
Some bootloaders configure the PRNG to 32MHz and others choose
64MHz. Support both so that we always vote for the correct
voltage.

Change-Id: Ifd2c47044b60b3743ed4e1939a4fe18ba7861695
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>