Upstream: reset parsing state after invalid status line

Previously, it was possible to start parsing headers with a wrong
parsing state after status line was not recognized, as a fallback
used in the scgi and uwsgi modules.

Reported by Leo Lin.

src/http/modules/ngx_http_scgi_module.c

@@ -1036,6 +1036,7 @@ ngx_http_scgi_process_status_line(ngx_http_request_t *r)
 
     if (rc == NGX_ERROR) {
         u->process_header = ngx_http_scgi_process_header;
+        r->state = 0;
         return ngx_http_scgi_process_header(r);
     }
 

src/http/modules/ngx_http_uwsgi_module.c

@@ -1275,6 +1275,7 @@ ngx_http_uwsgi_process_status_line(ngx_http_request_t *r)
 
     if (rc == NGX_ERROR) {
         u->process_header = ngx_http_uwsgi_process_header;
+        r->state = 0;
         return ngx_http_uwsgi_process_header(r);
     }