Use actual exec size when setting msg len

Use actual instruction execution size when setting dst, src0, src1 message length for send instructions.

Author: pratikashar

visa/VisaToG4/TranslateSendLdStLegacy.cpp

@@ -2543,20 +2543,20 @@ int IR_Builder::translateVISASVMAtomicInst(
   unsigned len = 0;
 
   sources[len].opnd = addresses;
-  sources[len].numElts = exSize;
+  sources[len].numElts = instExSize;
   sources[len].instOpt = instOpt;
   ++len;
 
   if (src0 != NULL && !src0->isNullReg()) {
     sources[len].opnd = src0;
-    sources[len].numElts = exSize;
+    sources[len].numElts = instExSize;
     sources[len].instOpt = instOpt;
     ++len;
   }
 
   if (src1 != NULL && !src1->isNullReg()) {
     sources[len].opnd = src1;
-    sources[len].numElts = exSize;
+    sources[len].numElts = instExSize;
     sources[len].instOpt = instOpt;
     ++len;
   }