AK: Convert AK::Format formatting helpers to returning ErrorOr<void>

This isn't a complete conversion to ErrorOr<void>, but a good chunk.
The end goal here is to propagate buffer allocation failures to the
caller, and allow the use of TRY() with formatting functions.

Userland/Utilities/syscall.cpp

@@ -28,7 +28,7 @@ static FlatPtr parse_from(ArgIter&);
 
 template<>
 struct AK::Formatter<Syscall::Function> : Formatter<StringView> {
-    void format(FormatBuilder& builder, Syscall::Function function)
+    ErrorOr<void> format(FormatBuilder& builder, Syscall::Function function)
     {
         return Formatter<StringView>::format(builder, to_string(function));
     }