[Wconversion] Suppress warnings

Bug: 56258
Bug: 58162
Change-Id: Ie0417f2aefb9e5a49a5cf45ef8c2842274e389e1
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/glog/+/422997
Reviewed-by: Petr Hosek <phosek@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index cb75d65..0dc7398 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -47,7 +47,10 @@
 
   if (current_os == "linux") {
     defines = [ "HAVE_SYSCALL_H" ]
-    cflags_cc = [ "-Wno-sign-compare" ]
+    cflags_cc = [
+      "-Wno-sign-compare",
+      "-Wno-conversion",
+    ]
   }
   cflags = [ "-Wno-conversion" ]
 }