video: fbdev: sm712fb.c: fixed constant-left comparison warning

Fixed a constant-left comparison warning issue check by
scripts/checkpatch.pl:
  WARNING: Comparisons should place the constant on the right side of the test
Signed-off-by: Lynn Lei <lynnl.wit@gmail.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Teddy Wang <teddy.wang@siliconmotion.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

drivers/video/fbdev/sm712fb.c

@@ -1478,7 +1478,7 @@ static int smtcfb_pci_probe(struct pci_dev *pdev,
 	}
 
 	/* can support 32 bpp */
-	if (15 == sfb->fb->var.bits_per_pixel)
+	if (sfb->fb->var.bits_per_pixel == 15)
 		sfb->fb->var.bits_per_pixel = 16;
 
 	sfb->fb->var.xres_virtual = sfb->fb->var.xres;