Chagne prof_accum_t to counter_accum_t for general purpose.

include/jemalloc/internal/prof_structs.h

@@ -21,15 +21,6 @@ typedef struct {
 } prof_unwind_data_t;
 #endif
 
-struct prof_accum_s {
-#ifndef JEMALLOC_ATOMIC_U64
-	malloc_mutex_t	mtx;
-	uint64_t	accumbytes;
-#else
-	atomic_u64_t	accumbytes;
-#endif
-};
-
 struct prof_cnt_s {
 	/* Profiling counters. */
 	uint64_t	curobjs;