range: Let 416s pass through

Reported by Simon as a followup to #3683.

bin/varnishd/cache/cache_range.c

@@ -300,6 +300,8 @@ VRG_CheckBo(struct busyobj *bo)
 	if (crlo < 0) {		// Content-Range: bytes */123
 		assert(crhi < 0);
 		assert(crlen > 0);
+		if (http_GetStatus(bo->beresp) == 416)
+			return (0);
 		crlo = 0;
 		crhi = crlen - 1;
 	}

bin/varnishtest/tests/c00034.vtc

@@ -245,6 +245,10 @@ server s1 {
 	expect req.http.range == "bytes=10-19"
 	txresp -status 206 -hdr "content-range: bytes 10-19/100" -bodylen 40
 
+	rxreq
+	expect req.http.range == "bytes=90-119"
+	txresp -status 416 -hdr "content-range: bytes */100" -bodylen 100
+
 	rxreq
 	expect req.url == "/?unexpected=content-range"
 	expect req.http.range == <undef>
@@ -279,6 +283,10 @@ client c8 {
 	rxresp
 	expect resp.status == 503
 
+	txreq -hdr "range: bytes=90-119" -hdr "return: pass"
+	rxresp
+	expect resp.status == 416
+
 	txreq -url "/?unexpected=content-range"
 	rxresp
 	expect resp.status == 503