drm/msm/mdp5: Remove set but not used variable 'fmt'

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

drivers/gpu/drm/msm/disp/mdp5/mdp5_smp.c: In function mdp5_smp_calculate:
drivers/gpu/drm/msm/disp/mdp5/mdp5_smp.c:134:6: warning: variable fmt set but not used [-Wunused-but-set-variable]

It is not used since commit 24c478ea ("drm/fourcc:
Pass the format_info pointer to drm_format_plane_cpp")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1570690506-83287-2-git-send-email-zhengbin13@huawei.com

drivers/gpu/drm/msm/disp/mdp5/mdp5_smp.c

@@ -121,7 +121,6 @@ uint32_t mdp5_smp_calculate(struct mdp5_smp *smp,
 	struct mdp5_kms *mdp5_kms = get_kms(smp);
 	int rev = mdp5_cfg_get_hw_rev(mdp5_kms->cfg);
 	int i, hsub, nplanes, nlines;
-	u32 fmt = format->base.pixel_format;
 	uint32_t blkcfg = 0;
 
 	nplanes = info->num_planes;
@@ -135,7 +134,6 @@ uint32_t mdp5_smp_calculate(struct mdp5_smp *smp,
 	 * them together, writes to SMP using a single client.
 	 */
 	if ((rev > 0) && (format->chroma_sample > CHROMA_FULL)) {
-		fmt = DRM_FORMAT_NV24;
 		nplanes = 2;
 
 		/* if decimation is enabled, HW decimates less on the