socket_options: prevent direct import of private header linux/in.h

This commit suppresses the warning to import the private header
`linux/in(6).h` directly. Otherwise this leads to the following
clangd error.

```
Redefinition of struct in6_addr
```

Signed-off-by: Marco Hofstetter <[email protected]>

Author: mhofstetter

.clangd

@@ -4,6 +4,10 @@ Index:
 Diagnostics:
   UnusedIncludes: Strict
   MissingIncludes: Strict
+  Includes:
+    IgnoreHeader:
+      - "linux/in\\.h"
+      - "linux/in6\\.h"
 # CompileFlags:
 #   CompilationDatabase: ./compile_commands.json
 #   # Unfortunately, above config isn't working as expected.

cilium/socket_option.h

@@ -1,8 +1,6 @@
 #pragma once
 
 #include <asm-generic/socket.h>
-#include <linux/in.h>
-#include <linux/in6.h>
 #include <netinet/in.h>
 
 #include <cerrno>