drm/msm/mdp5: Remove set but not used variable 'hw_cfg' in modeset_init

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c: In function modeset_init:
drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c:458:28: warning: variable hw_cfg set but not used [-Wunused-but-set-variable]

It is not used since commit 36d1364a ("drm/msm/mdp5:
Clean up interface assignment")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1570630403-92371-1-git-send-email-zhengbin13@huawei.com

drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c

@@ -461,14 +461,11 @@ static int modeset_init(struct mdp5_kms *mdp5_kms)
 {
 	struct drm_device *dev = mdp5_kms->dev;
 	struct msm_drm_private *priv = dev->dev_private;
-	const struct mdp5_cfg_hw *hw_cfg;
 	unsigned int num_crtcs;
 	int i, ret, pi = 0, ci = 0;
 	struct drm_plane *primary[MAX_BASES] = { NULL };
 	struct drm_plane *cursor[MAX_BASES] = { NULL };
 
-	hw_cfg = mdp5_cfg_get_hw_config(mdp5_kms->cfg);
-
 	/*
 	 * Construct encoders and modeset initialize connector devices
 	 * for each external display interface.