do not delete resolver sources from release tarball

misc/GNUmakefile

diff --git a/misc/GNUmakefile b/misc/GNUmakefile
index 066be77..b863d67 100644
--- a/misc/GNUmakefile
+++ b/misc/GNUmakefile
@@ -18,8 +18,6 @@
 	rm $(TEMP)/$(NGINX)/src/event/modules/ngx_iocp_module.*
 	rm -r $(TEMP)/$(NGINX)/src/os/win32
 
-	rm $(TEMP)/$(NGINX)/src/core/ngx_resolver.*
-
 	rm -r $(TEMP)/$(NGINX)/src/mysql
 
 	rm $(TEMP)/$(NGINX)/src/http/modules/ngx_http_status_module.c