profiler: Fix compilation errors

Fix below compilation error with clang
warning: attribute 'packed' is ignored, place it after
"union" to apply attribute to type  declaration
[-Wignored-attributes].

Change-Id: Id8cebb3d60b61d8d2168b8f8d77c79107edb4953
Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>