ARM: dts: msm: increase number of bw scale event ring elements

Double the number of event ring elements for special purpose
event ring such as BW scaling to accommodate extra events from
a speedy producer.

Change-Id: I6a579528b17a49f0e7eba14cb6a200e8486f6d32
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>