* include/endian.h: Move definitions of __BIG_ENDIAN, __LITTLE_ENDIAN,

	* include/endian.h: Move definitions of __BIG_ENDIAN, __LITTLE_ENDIAN,
	and __BYTE_ORDER into ...
	* include/bits/endian.h: New file.
	* include/arpa/nameser_compat.h: Include endian.h rather than defining
	BYTE_ORDER here.
	* include/asm/byteorder.h: Include bits/endian.h.  Drop definition of
	__LITTLE_ENDIAN.
	* include/netinet/ip.h: Include bits/endian.h.  Drop definitions of
	BIG_ENDIAN, LITTLE_ENDIAN, and BYTE_ORDER.  Use underscored variants
	of aforementioned constants.
	* include/netinet/tcp.h: Ditto.
	* include/sys/param.h: Drop disabled definitions of BIG_ENDIAN,
	LITTLE_ENDIAN, and BYTE_ORDER.

	* include/netinet/ip.h: Reformat.  Define setsockopt IP_TOS options
	matching recent RFCs.  Tweak comments.