nginx: Enhanced nginx.conf to explicitly disable uwsgi module if uwsgi is not installed.

network/nginx/nginx.conf

@@ -47,7 +47,7 @@ for x in openssl:ssl libgd:image_filter zlib:gzip_static; do
 done
 
 # --without- because of dependency
-for x in pcre:http_rewrite_module openssl:http-cache; do
+for x in pcre:http_rewrite_module openssl:http-cache uwsgi:http_uwsgi_module; do
 	if ! pkginstalled "${x%:*}"; then
 		var_append confopt ' ' "--without-${x#*:}"
 	fi