msm: gemini: Fix the size argument of hw_region_dump function.

The size argument for the msm_gemini_hw_region_dump function is
signed which is not correct, since the function operates on
it as if it is unsigned. Change this to unsigned parameter.

Change-Id: Icea70ad20b010651047b911e7b6ae57889e610e7
Signed-off-by: Kiran Kumar H N <hurlisal@codeaurora.org>