Update HsaMemFlags.ui32.CoarseGrain comment

As advised by Paul Blinzer

Change-Id: Icabf4acd94866ddbbe53faf48a71e1113f0c76b6


[ROCm/ROCR-Runtime commit: b94ae66c62]

projects/rocr-runtime/include/hsakmttypes.h

@@ -453,9 +453,11 @@ typedef struct _HsaMemFlags
             unsigned int ExecuteAccess: 1; // default = 0: Identifies if memory is primarily used for data or accessed 
                                            // for executable code (e.g. queue memory) by the host CPU or the device. 
                                            // Influences the page attribute setting within the allocation
-            unsigned int CoarseGrain : 1;  // default = 0: Memory is assigned explicitly to one agent at a time and does
-                                           // not need to be accessed in a cache-coherent way. Memory consistency needs
-                                           // to be enforced at synchronization points at dispatch boundaries.
+            unsigned int CoarseGrain : 1;  // default = 0: The memory can be accessed assuming cache
+                                           // coherency maintained by link infrastructure and HSA agents.
+                                           // 1: memory consistency needs to be enforced at
+                                           // synchronization points at dispatch or other software
+                                           // enforced synchronization boundaries.
             unsigned int Reserved    : 18;
 
         } ui32;