fbmem: fix con2fbmap limit check

Fix limit check in FBIOPUT_CON2FBMAP ioctl.

Signed-off-by: Peter Samuelson <peter@p12n.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/fbmem.c

@@ -1057,7 +1057,7 @@ fb_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 	case FBIOPUT_CON2FBMAP:
 		if (copy_from_user(&con2fb, argp, sizeof(con2fb)))
 			return - EFAULT;
-		if (con2fb.console < 0 || con2fb.console > MAX_NR_CONSOLES)
+		if (con2fb.console < 1 || con2fb.console > MAX_NR_CONSOLES)
 		    return -EINVAL;
 		if (con2fb.framebuffer < 0 || con2fb.framebuffer >= FB_MAX)
 		    return -EINVAL;