ARM: dts: fix duplicated build target and alphabetical sort out for exynos

Commit db5b0ae0 ("Merge tag 'dt' of git://git.kernel.org/.../arm-soc"

)
causes a duplicated build target.  This patch fixes it and sorts out the
build target alphabetically so that we can recognize something wrong
easily.

Cc: Olof Johansson <olof@lixom.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>