We already have, as a result of upstreaming the gpu bindings,
msm_clk_get() which will try to get the clock both without and with a
"_clk" suffix.  Use this in DSI code so we can drop the "_clk" suffix
in bindings while maintaing backwards compatibility.
Signed-off-by: NRob Clark <robdclark@gmail.com>
Reviewed-by: NSean Paul <seanpaul@chromium.org>