drm: msm: fix compilation error

drivers/gpu/drm/msm/dsi-staging/dsi_panel.c:3387:31:
error: a function declaration without a prototype is deprecated in all
versions of C [-Werror,-Wstrict-prototypes]
static bool ufshcd_get_hwlevel()
                              ^
                               void

Change-Id: Ia18e7fa0a5bd0ff53eb94b39d50576c8ba1ff9c5
Signed-off-by: Skyblueborb <tomaszborbely0710@gmail.com>