[media] au8522: Fix off-by-one in SNR table for QAM256

The table of valid SNR values for QAM 256 is off by one, and as a result
if the SNR is oscillating between 40.0 and 39.9 dB, tools like azap show
it going back and forth between 40.0 and 0 (misleading some people,
including myself, to think signal lock is being lost or there is a
problem with register reads).

Fix the table so that 40.0 dB is properly represented.

Cc: Steven Toth <stoth@kernellabs.com>
Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/dvb/frontends/au8522_dig.c

@@ -157,54 +157,54 @@ static struct mse2snr_tab qam64_mse2snr_tab[] = {
 
 /* QAM256 SNR lookup table */
 static struct mse2snr_tab qam256_mse2snr_tab[] = {
-	{  16,   0 },
-	{  17, 400 },
-	{  18, 398 },
-	{  19, 396 },
-	{  20, 394 },
-	{  21, 392 },
-	{  22, 390 },
-	{  23, 388 },
-	{  24, 386 },
-	{  25, 384 },
-	{  26, 382 },
-	{  27, 380 },
-	{  28, 379 },
-	{  29, 378 },
-	{  30, 377 },
-	{  31, 376 },
-	{  32, 375 },
-	{  33, 374 },
-	{  34, 373 },
-	{  35, 372 },
-	{  36, 371 },
-	{  37, 370 },
-	{  38, 362 },
-	{  39, 354 },
-	{  40, 346 },
-	{  41, 338 },
-	{  42, 330 },
-	{  43, 328 },
-	{  44, 326 },
-	{  45, 324 },
-	{  46, 322 },
-	{  47, 320 },
-	{  48, 319 },
-	{  49, 318 },
-	{  50, 317 },
-	{  51, 316 },
-	{  52, 315 },
-	{  53, 314 },
-	{  54, 313 },
-	{  55, 312 },
-	{  56, 311 },
-	{  57, 310 },
-	{  58, 308 },
-	{  59, 306 },
-	{  60, 304 },
-	{  61, 302 },
-	{  62, 300 },
-	{  63, 298 },
+	{  15,   0 },
+	{  16, 400 },
+	{  17, 398 },
+	{  18, 396 },
+	{  19, 394 },
+	{  20, 392 },
+	{  21, 390 },
+	{  22, 388 },
+	{  23, 386 },
+	{  24, 384 },
+	{  25, 382 },
+	{  26, 380 },
+	{  27, 379 },
+	{  28, 378 },
+	{  29, 377 },
+	{  30, 376 },
+	{  31, 375 },
+	{  32, 374 },
+	{  33, 373 },
+	{  34, 372 },
+	{  35, 371 },
+	{  36, 370 },
+	{  37, 362 },
+	{  38, 354 },
+	{  39, 346 },
+	{  40, 338 },
+	{  41, 330 },
+	{  42, 328 },
+	{  43, 326 },
+	{  44, 324 },
+	{  45, 322 },
+	{  46, 320 },
+	{  47, 319 },
+	{  48, 318 },
+	{  49, 317 },
+	{  50, 316 },
+	{  51, 315 },
+	{  52, 314 },
+	{  53, 313 },
+	{  54, 312 },
+	{  55, 311 },
+	{  56, 310 },
+	{  57, 308 },
+	{  58, 306 },
+	{  59, 304 },
+	{  60, 302 },
+	{  61, 300 },
+	{  62, 298 },
 	{  65, 295 },
 	{  68, 294 },
 	{  70, 293 },