Try to unbreak build after https://swiftshader-review.googlesource.com/c/SwiftShader/+/55608

Change-Id: I412ad6b4b384bef7ab43270922eed2256d4fb62b
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/55648
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Nico Weber <thakis@google.com>
Tested-by: Nico Weber <thakis@google.com>
Commit-Queue: Nico Weber <thakis@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index 5f98398..9fb4254 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -19,7 +19,9 @@
 import("src/Reactor/reactor.gni")
 
 config("swiftshader_config") {
+  cflags = []
   defines = []
+  ldflags = []
 
   if (!is_debug) {
     defines += [ "ANGLE_DISABLE_TRACE" ]
@@ -46,7 +48,7 @@
 
     cflags_cc = [ "/std:c++17" ]
   } else {
-    cflags = [ "-fno-operator-names" ]
+    cflags += [ "-fno-operator-names" ]
     cflags_cc = [ "-std=c++17" ]
 
     defines +=