configure: also check for byteswap.h
configure: also check for byteswap.h

include/f2fs_fs.h checks the HAVE_BYTESWAP_H conditional, but it is
never checked for in configure.

Add that header to the list of headers checked for.

Signed-off-by: "Yann E. MORIN" <b375a36861a21dce61868a5a9b415811d17b4e97@free.fr>
Cc: Gustavo Zacarias <beac5f8171fcde5e2ec734cc5d25d03e7362e8de@zacarias.com.ar>
Signed-off-by: Jaegeuk Kim <71255387a32c360dfbe6dfb7aaeb123bf1dc8cb6@kernel.org>

Infinitive-OS/external_f2fs-tools,OneRom/external_f2fs-tools,PAC-ROM/android_external_f2fs-tools,Infinitive-OS/platform_external_f2fs-tools,NamelessRom/android_external_f2fs-tools,TeamTwisted/android_external_f2fs-tools,geekboxzone/mmallow_external_f2fs-tools,TurboROM/external_f2fs-tools,YUPlayGodDev/platform_external_f2fs-tools,YUPlayGodDev/platform_external_f2fs-tools,DARKPOP/external_f2fs-tools,DARKPOP/external_f2fs-tools,Yu-AndroidM/android_external_f2fs-tools,Infinitive-OS/external_f2fs-tools,NamelessRom/android_external_f2fs-tools,blastagator/cm_external_f2fs-tools,PAC-ROM/android_external_f2fs-tools,geekboxzone/mmallow_external_f2fs-tools,TeamExodus/external_f2fs-tools,TeamExodus/external_f2fs-tools,TeamTwisted/android_external_f2fs-tools,Infinitive-OS/platform_external_f2fs-tools,Yu-AndroidM/android_external_f2fs-tools,AOSP-YU/platform_external_f2fs-tools,OneRom/external_f2fs-tools,blastagator/cm_external_f2fs-tools,TurboROM/external_f2fs-tools,AOSP-YU/platform_external_f2fs-tools