Eliminate some -Wabsolute-value compiler warnings

sizeField() returns a sqInt.
sqInt is 64bits long on 64bits images.
Taking abs(sqInt) will truncate the size to 32bits.

That's probably benign because the size will rarely exceed 2^31, so we effectively truncate nothing.
But we have a correct way to take absolute value of sqInt (SQABS) and long (labs) so let's just use them and eliminate the false positive warnings.

platforms/Cross/plugins/IA32ABI/dax64business.h

@@ -28,7 +28,7 @@
 			sqInt arg = argVector[i + 1];
 			if (objIsAlien(arg) && (sizeField(arg) != 0))
 				/* Direct or indirect Alien. */
-                        	size += RoundUpPowerOfTwo(abs(sizeField(arg)), 8);
+                        	size += RoundUpPowerOfTwo(SQABS(sizeField(arg)), 8);
 			else if (interpreterProxy->isFloatObject(arg))
 				size += sizeof(double);
 			else 
@@ -42,7 +42,7 @@
 			sqInt arg = argVector[i];
 			if (objIsAlien(arg) && (sizeField(arg) != 0))
 				/* Direct or indirect Alien. */
-                          size += RoundUpPowerOfTwo(abs(sizeField(arg)), 8);
+                          size += RoundUpPowerOfTwo(SQABS(sizeField(arg)), 8);
 			else if (interpreterProxy->isFloatObject(arg))
 				size += sizeof(double);
 			else
@@ -87,7 +87,7 @@
 				if ((size = sizeField(arg)) == 0) /* Pointer Alien. */
 					size = argByteSize = sizeof(void *);
 				else /* Direct or indirect Alien. */
-					argByteSize = abs(size);
+					argByteSize = labs(size);
 				if ((argByteSize <= sizeof(long)) && (nextReg < NUM_REG_ARGS)) {
 					regs[nextReg++] = *(long*)startOfDataWithSize(arg, size);
 				}
@@ -129,7 +129,7 @@
 				if ((size = sizeField(arg)) == 0) /* Pointer Alien. */
 					size = argByteSize = sizeof(void *);
 				else /* Direct or indirect Alien. */
-					argByteSize = abs(size);
+					argByteSize = labs(size);
 				if ((argByteSize <= sizeof(long)) && (nextReg < NUM_REG_ARGS)) {
 					regs[nextReg++] = *(long*)startOfDataWithSize(arg, size);
 				}
@@ -188,7 +188,7 @@
 			size = sizeof(long);
 		memcpy(startOfDataWithSize(resultMaybeAlien, size),
 			   &r,
-			   min((unsigned)abs(size), sizeof(r)));
+			   min((unsigned long)labs(size), sizeof(r)));
 	}
 
 	return PrimNoErr;