Update libjpeg-turbo.

jcdctmgr.c

 /*
  * jcdctmgr.c
  *
  * Copyright (C) 1994-1996, Thomas G. Lane.
  * Copyright (C) 1999-2006, MIYASAKA Masaru.
  * Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
  * Copyright (C) 2011 D. R. Commander
  * This file is part of the Independent JPEG Group's software.
  * For conditions of distribution and use, see the accompanying README file.
  *
@@ skipping 164 matching lines @@
 
   fq = ((UDCTELEM2)1 << r) / divisor;
   fr = ((UDCTELEM2)1 << r) % divisor;
 
   c = divisor / 2; /* for rounding */
 
   if (fr == 0) { /* divisor is power of two */
     /* fq will be one bit too large to fit in DCTELEM, so adjust */
     fq >>= 1;
     r--;
-  } else if (fr <= (divisor / 2)) { /* fractional part is < 0.5 */
+  } else if (fr <= (divisor / 2U)) { /* fractional part is < 0.5 */
     c++;
   } else { /* fractional part is > 0.5 */
     fq++;
   }
 
   dtbl[DCTSIZE2 * 0] = (DCTELEM) fq;      /* reciprocal */
   dtbl[DCTSIZE2 * 1] = (DCTELEM) c;       /* correction + roundfactor */
   dtbl[DCTSIZE2 * 2] = (DCTELEM) (1 << (sizeof(DCTELEM)*8*2 - r));  /* scale */
   dtbl[DCTSIZE2 * 3] = (DCTELEM) r - sizeof(DCTELEM)*8; /* shift */
 
@@ skipping 437 matching lines @@
                                   SIZEOF(DCTELEM) * DCTSIZE2);
 
   /* Mark divisor tables unallocated */
   for (i = 0; i < NUM_QUANT_TBLS; i++) {
     fdct->divisors[i] = NULL;
 #ifdef DCT_FLOAT_SUPPORTED
     fdct->float_divisors[i] = NULL;
 #endif
   }
 }