drm/msm/hdmi: Drop pointless static qualifier in msm_hdmi_bind()

There is no need to have the 'struct hdmi_platform_config *hdmi_cfg'
variable static since new value always be assigned before use it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>