drm/radeon/r600: Strip out set but unused 'tmp' variables

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/radeon/r600.c: In function ‘r600_pcie_gart_tlb_flush’:
 drivers/gpu/drm/radeon/r600.c:1083:7: warning: variable ‘tmp’ set but not used [-Wunused-but-set-variable]
 drivers/gpu/drm/radeon/r600.c: At top level:
 drivers/gpu/drm/radeon/r600.c: In function ‘r600_mmio_hdp_flush’:
 drivers/gpu/drm/radeon/r600.c:4393:7: warning: variable ‘tmp’ set but not used [-Wunused-but-set-variable]

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/r600.c

@@ -1080,7 +1080,6 @@ void r600_pcie_gart_tlb_flush(struct radeon_device *rdev)
 	if ((rdev->family >= CHIP_RV770) && (rdev->family <= CHIP_RV740) &&
 	    !(rdev->flags & RADEON_IS_AGP)) {
 		void __iomem *ptr = (void *)rdev->gart.ptr;
-		u32 tmp;
 
 		/* r7xx hw bug.  write to HDP_DEBUG1 followed by fb read
 		 * rather than write to HDP_REG_COHERENCY_FLUSH_CNTL
@@ -1088,7 +1087,7 @@ void r600_pcie_gart_tlb_flush(struct radeon_device *rdev)
 		 * method for them.
 		 */
 		WREG32(HDP_DEBUG1, 0);
-		tmp = readl((void __iomem *)ptr);
+		readl((void __iomem *)ptr);
 	} else
 		WREG32(R_005480_HDP_MEM_COHERENCY_FLUSH_CNTL, 0x1);
 
@@ -4390,10 +4389,9 @@ void r600_mmio_hdp_flush(struct radeon_device *rdev)
 	if ((rdev->family >= CHIP_RV770) && (rdev->family <= CHIP_RV740) &&
 	    rdev->vram_scratch.ptr && !(rdev->flags & RADEON_IS_AGP)) {
 		void __iomem *ptr = (void *)rdev->vram_scratch.ptr;
-		u32 tmp;
 
 		WREG32(HDP_DEBUG1, 0);
-		tmp = readl((void __iomem *)ptr);
+		readl((void __iomem *)ptr);
 	} else
 		WREG32(R_005480_HDP_MEM_COHERENCY_FLUSH_CNTL, 0x1);
 }