ARM: sti: Staticize local variables

Symbols local to this file are made static.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Sachin Kamat <sachin.kamat@samsung.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Cc: kernel@stlinux.com
Cc: Srinivas Kandagatla <srinivas.kandagatla@gmail.com>
Cc: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Olof Johansson <olof@lixom.net>