include/linux/byteorder: Always defines __fswab64, __swab64p and __swab64s

When __BYTEORDER_HAS_U64__ is not defined, we got warning following:

-----
/tmp/include/linux/byteorder/little_endian.h: In function ‘__cpu_to_be64p’:
/tmp/include/linux/byteorder/little_endian.h:71:2: warning: implicit declaration of function ‘__swab64p’
		[-Wimplicit-function-declaration]
-----

Usually, __arch__swab64* required for __fswab64,  __swab64p and __swab64s
is defined.  Therefore, __BYTEORDER_HAS_U64__ is unnecessary.
This removes __BYTEORDER_HAS_U64__.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
CC: Kim Phillips <kim.phillips@freescale.com>
Reviewed-by: NKim Phillips <kim.phillips@freescale.com>

include/linux/byteorder/swab.h

@@ -122,7 +122,6 @@ static __inline__ void __swab32s(__u32 *addr)
 	__arch__swab32s(addr);
 }
 
-#ifdef __BYTEORDER_HAS_U64__
 static __inline__ __attribute__((const)) __u64 __fswab64(__u64 x)
 {
 #  ifdef __SWAB_64_THRU_32__
@@ -141,7 +140,6 @@ static __inline__ void __swab64s(__u64 *addr)
 {
 	__arch__swab64s(addr);
 }
-#endif /* __BYTEORDER_HAS_U64__ */
 
 #if defined(__KERNEL__)
 #define swab16 __swab16