7079329: Adjust allocation prefetching for T4
Summary: on T4 2 BIS instructions should be issued to prefetch 64 bytes
Reviewed-by: iveresov, phh, twisti
-export:JNI_GetDefaultJavaVMInitArgs
-export:JNI_CreateJavaVM
-export:JNI_GetCreatedJavaVMs
-export:jio_snprintf
-export:jio_printf
-export:jio_fprintf
-export:jio_vfprintf
-export:jio_vsnprintf