soc: qcom: glink: Increase number of log pages

Three pages of log history in insufficent to capture the complete history
of some issues which hampers analysis.  Increase the number of log pages to
fifteen to provide ample history for debugging issues.

Change-Id: I04e04f9dca84907995e200501dea9ab4a882f720
Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>