[Encode] Update LA_STATS_SIZE to fixed value

Changed LA_STATS_SIZE from calculated value (32 * 2) to hardcoded 480. This removes the comment about enlarging size for VdencHevcLaStats future usage and replaces the expression with its evaluated result. The change maintains the same buffer size (480 bytes) but makes the constant more explicit and removes dependency on the previous calculation rationale.

Author: chenhao5-Intel

_studio/shared/enctools/include/mfxenctools-int.h

@@ -41,7 +41,7 @@ extern "C"
 #endif /* __cplusplus */
 
 #define LA_DATA_ENTRY_NUM    128
-#define LA_STATS_SIZE        32 * 2 //enlarge the size to 2 * sizeof(VdencHevcLaStats) for further usage
+#define LA_STATS_SIZE        480
 #define LA_DATA_BUFFER_SIZE  LA_DATA_ENTRY_NUM * LA_STATS_SIZE
 
 /* Extended Buffer Ids */