mach: put logFn function to std_options

src/platform/wasm/entry.zig

@@ -28,7 +28,8 @@ fn writeLog(_: void, msg: []const u8) LogError!usize {
     return msg.len;
 }
 
-pub fn log(
+pub const std_options = struct {
+    pub fn logFn(
         comptime message_level: std.log.Level,
         comptime scope: @Type(.EnumLiteral),
         comptime format: []const u8,
@@ -40,6 +41,7 @@ pub fn log(
         writer.print(message_level.asText() ++ prefix ++ format ++ "\n", args) catch return;
         js.machLogFlush();
     }
+};
 
 pub fn panic(msg: []const u8, error_return_trace: ?*std.builtin.StackTrace, ret_addr: ?usize) noreturn {
     _ = error_return_trace;