LibC: Stub out fwide()

This is a mess, and I'd rather not perform checks on every single stdio
operation, so just make it a noop.

Userland/Libraries/LibC/wchar.h

@@ -77,5 +77,6 @@ wint_t getwchar(void);
 wint_t fputwc(wchar_t wc, FILE* stream);
 wint_t putwc(wchar_t wc, FILE* stream);
 wint_t putwchar(wchar_t wc);
+int fwide(FILE* stream, int mode);
 
 __END_DECLS

Userland/Libraries/LibC/wstdio.cpp

@@ -17,6 +17,12 @@ static_assert(AssertSize<wchar_t, sizeof(u32)>());
 
 extern "C" {
 
+int fwide(FILE*, int mode)
+{
+    // Nope Nope Nope.
+    return mode;
+}
+
 wint_t fgetwc(FILE* stream)
 {
     VERIFY(stream);