ypserv_xdr, as generated by rpcgen from yp.x with one major exception.

ypserv_xdr, as generated by rpcgen from yp.x with one major exception.
in xdr_ypresp_key_val() invert the order of loading the key and value
(rpcgen says [1] stat, [2] key, [3] value, but the data on the wire
 comes in as [1] stat, [2] val, [3] key...  you can't fix this in yp.x
 because if you invert the ordr in yp.x not only does it invert the order
 in ypserv_xdr.c, but it also inverts it in the structure in yp.h which
 cancels out the inversion in ypserv_xdr.c.   i guess this means it
 is not possible to have a yp.x that descrives the YP protocol properly?).

***NOTE*** this file is also needed because some of the YP functions in
libc are broken.   For example, compare src/lib/libc/yp/xdryp.c's version
of xdr_domainname() to the one in this file generated by rpcgen.  Note
that xdryp.c calls:
	 if (!xdr_string(xdrs, &objp, YPMAXDOMAIN)) { /* xdryp.c */
while ypserv_xdr.c (generated by rpcgen) calls:
	 if (!xdr_string(xdrs, objp, YPMAXDOMAIN)) { /* rpcgen */
(note the lack of "&" in the second line).   Clearly libc is wrong and
needs to be fixed (XXX).    (Of course changing libc could break other
YP stuff, which is why I haven't attemped it... :) )    When libc is
fixed, it should be possible to phase out this file, I think.