gpio/samsung: fix the typo 'exynos5_xxx' instead of 'exonys5_xxx'

Should be 'exynos5_xxx' instead of 'exonys5_xxx'.

It happened at the commit 30b84288 ("Merge tag 'soc2' of
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc"

)
during v3.5 merge window.

Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
[ My bad  - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>