Missing includes in dlls/wininet/netconnection.c

[Pavel Roskin]

Hello, Robert!

I'm sorry, but you keep breaking Wine for me.  The latest change in
dlls/wininet/netconnection.c (revision 1.18) doesn't compile.  Two files
need to be included - errno.h for error names and stdio.h for perror().

Actually, I think perror() should be avoided - Wine has its own error
reporting mechanisms.  But to be fair, there are instances of perror()
in the current Wine code.