allow Destination URL without host

src/http/modules/ngx_http_dav_module.c

diff --git a/src/http/modules/ngx_http_dav_module.c b/src/http/modules/ngx_http_dav_module.c
index 3d34a40..0761c16 100644
--- a/src/http/modules/ngx_http_dav_module.c
+++ b/src/http/modules/ngx_http_dav_module.c
@@ -535,6 +535,13 @@
         return NGX_HTTP_BAD_REQUEST;
     }
 
+    p = dest->value.data;
+    /* there is always '\0' even after empty header value */
+    if (p[0] == '/') {
+        last = p + dest->value.len;
+        goto destination_done;
+    }
+
     len = r->headers_in.server.len;
 
     if (len == 0) {