netload warnings (+disable on OpenBSD ?)

updating systemload to 1.3.1 on OpenBSD, i'm sorry to say things arent fully great.

first there's a warning in netload code:

network.c:127:28: warning: incompatible pointer types passing 'guint64 *' (aka 'unsigned long long *') to parameter of type 'gulong *' (aka 'unsigned long *') [-Wincompatible-pointer-types]                        
    if (read_netload_proc (&bytes[1]) != 0)                                                                                                                                                                          
                           ^~~~~~~~~                                                                                                                                                                                 
network.c:73:28: note: passing argument to parameter 'bytes' here                                                                                                                                                    
read_netload_proc (gulong *bytes)                                                                                                                                                                                    
                           ^                                                                                                                                                                                         
network.c:128:35: warning: incompatible pointer types passing 'guint64 *' (aka 'unsigned long long *') to parameter of type 'gulong *' (aka 'unsigned long *') [-Wincompatible-pointer-types]                        
        if (read_netload_libgtop (&bytes[1]) != 0)                                                                                                                                                                   
                                  ^~~~~~~~~                                                                                                                                                                          
network.c:63:31: note: passing argument to parameter 'bytes' here                                                                                                                                                    
read_netload_libgtop (gulong *bytes)  

second, libgtop on OpenBSD doesnt implement the required function for netload

glibtop(c=40484): [ERROR] glibtop_get_netload: Function not implemented

which sorta makes sense as to be able to have "netload" one would have to choose a network interface first (eg a bit like it was done in xfce4-netload-plugin#2), i dont think there's a notion of "systemwide network load" anywhere.

so sadly until there's a way to "select an interface" i'll probably disable libgtop detection & patch out the network bits in our port.

edit sorry i hadnt read the code first in network.c which properly iterates over all existing interfaces.