Remove unused variables

cppcheck flags style warnings to indicate when we declare a variable and
never use it. Its effective dead code, this patch aims at fixing all the
[unusedVariable] warnings reported by the openbmc repo-ci.

Change-Id: Ie51176c6b2ced7251b467b2d456e9f3088637121
Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>