[ARM] 3758/1: Preserve signalling NaNs in conversion

Patch from Daniel Jacobowitz

The fcvtds and fcvtsd instructions were generating a qnan bit pattern
for both quiet and signalling NaNs.
Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/vfp/vfpdouble.c

@@ -465,7 +465,7 @@ static u32 vfp_double_fcvts(int sd, int unused, int dm, u32 fpscr)
 	 */
 	if (tm & (VFP_INFINITY|VFP_NAN)) {
 		vsd.exponent = 255;
-		if (tm & VFP_NAN)
+		if (tm == VFP_QNAN)
 			vsd.significand |= VFP_SINGLE_SIGNIFICAND_QNAN;
 		goto pack_nan;
 	} else if (tm & VFP_ZERO)

arch/arm/vfp/vfpsingle.c

@@ -506,7 +506,7 @@ static u32 vfp_single_fcvtd(int dd, int unused, s32 m, u32 fpscr)
 	 */
 	if (tm & (VFP_INFINITY|VFP_NAN)) {
 		vdd.exponent = 2047;
-		if (tm & VFP_NAN)
+		if (tm == VFP_QNAN)
 			vdd.significand |= VFP_DOUBLE_SIGNIFICAND_QNAN;
 		goto pack_nan;
 	} else if (tm & VFP_ZERO)