Fix a warning that was reported by the kernel test robot:

In file included from ../include/math-emu/soft-fp.h:27,
                 from ../arch/sh/math-emu/math.c:22:
../arch/sh/include/asm/sfp-machine.h:17: warning: "__BYTE_ORDER" redefined
   17 | #define __BYTE_ORDER __BIG_ENDIAN
In file included from ../arch/sh/math-emu/math.c:21:
../arch/sh/math-emu/sfp-util.h:71: note: this is the location of the previous definition
   71 | #define __BYTE_ORDER __LITTLE_ENDIAN

Fixes: b929926f ("sh: define __BIG_ENDIAN for math-emu")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Link: lore.kernel.org/r/202111121827.6v6SXtVv-lkp@intel.com
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: linux-sh@vger.kernel.org
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable@vger.kernel.org
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/20230306040037.20350-5-rdunlap@infradead.orgSigned-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>