Revert "msm: ion: fix ion cache maintenance issue"

This reverts commit afedf4f2("msm: ion: fix ion cache
maintenance issue") was causing device crash just after
launching camera or adrenotest app. revert the change
till original issue get fixed.

Change-Id: I32e9ff9610de7de8f24fae36ed14ff35a9806f0c
Signed-off-by: Fnu Yagyasen <yagya@codeaurora.org>