CLEANUP: remove trashlen

trashlen is a copy of global.tune.bufsize, so let's stop using it as
a duplicate, fall back to the original bufsize, it's less confusing
this way.
diff --git a/src/dumpstats.c b/src/dumpstats.c
index d0f0345..21517be 100644
--- a/src/dumpstats.c
+++ b/src/dumpstats.c
@@ -599,7 +599,7 @@
 	case STAT_CLI_O_TAB:
 		if (!ts)
 			return;
-		chunk_init(&msg, trash, trashlen);
+		chunk_init(&msg, trash, global.tune.bufsize);
 		if (!stats_dump_table_head_to_buffer(&msg, si, px, px))
 			return;
 		stats_dump_table_entry_to_buffer(&msg, si, px, ts);
@@ -1026,7 +1026,7 @@
 			}
 
 			/* return server's effective weight at the moment */
-			snprintf(trash, trashlen, "%d (initial %d)\n", sv->uweight, sv->iweight);
+			snprintf(trash, global.tune.bufsize, "%d (initial %d)\n", sv->uweight, sv->iweight);
 			bi_putstr(si->ib, trash);
 			return 1;
 		}
@@ -1495,7 +1495,7 @@
 			if (buffer_almost_full(si->ib->buf))
 				break;
 
-			reql = bo_getline(si->ob, trash, trashlen);
+			reql = bo_getline(si->ob, trash, global.tune.bufsize);
 			if (reql <= 0) { /* closed or EOL not found */
 				if (reql == 0)
 					break;
@@ -1668,7 +1668,7 @@
 	struct chunk msg;
 	unsigned int up;
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	switch (si->conn.xprt_st) {
 	case STAT_ST_INIT:
@@ -1784,7 +1784,7 @@
 	struct session *s = si->conn.xprt_ctx;
 	struct chunk msg;
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	switch (si->conn.xprt_st) {
 	case STAT_ST_INIT:
@@ -1888,7 +1888,7 @@
 	struct chunk msg;
 	unsigned int up;
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	switch (si->conn.xprt_st) {
 	case STAT_ST_INIT:
@@ -2258,7 +2258,7 @@
 	struct listener *l;
 	struct chunk msg;
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	switch (si->applet.ctx.stats.px_st) {
 	case STAT_PX_ST_INIT:
@@ -3315,7 +3315,7 @@
 	extern const char *monthname[12];
 	char pn[INET6_ADDRSTRLEN];
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 	sess = si->applet.ctx.sess.target;
 
 	if (si->applet.ctx.sess.section > 0 && si->applet.ctx.sess.uid != sess->uniq_id) {
@@ -3569,7 +3569,7 @@
 		return 1;
 	}
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	switch (si->conn.xprt_st) {
 	case STAT_ST_INIT:
@@ -3790,7 +3790,7 @@
 		return 1;
 	}
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	while (si->conn.xprt_st != STAT_ST_FIN) {
 		switch (si->conn.xprt_st) {
@@ -3985,7 +3985,7 @@
 	if (unlikely(si->ib->flags & (CF_WRITE_ERROR|CF_SHUTW)))
 		return 1;
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	if (!si->applet.ctx.errors.px) {
 		/* the function had not been called yet, let's prepare the