[lwip-members] RFC: ntohs HTONS

[Jani Monoses]

I propose sticking to lowercase equivalents of this.
HTONS & co are in BSD variants used to change byte order in one statement
like this

HTONS(hdr->field);
the equivalent of
hdr->field = htons(hdr->field);

So we can have the uppercase variants but then we should use them as such.
I don't think the differences are to hint at compilers about the constant 
nature of the argument

So if nobody objects I'll
1) make all lwip code use lowercase 
2) put ntohs functions in inet.c so arch only define them if want to optimize
3) optionally put in uppercase if they match the use case above.

Comments?

Linux headers don't even seem to define upper case variants at all.