Update Files
Revert "lib/memcopy: use glibc version"

This reverts commit 5ada46d478c178312c3ebd97b88ab4741c199c49.
Revert "lib/string: use glibc version"

This reverts commit bbd30a3cfff02ae3d6b868ee4e2fb61430138898.
btree: fix tree corruption in btree_get_prev()
lib/gcd.c: prevent possible div by 0
idr: fix a subtle bug in idr_get_next()
lib/rwsem.c: steal writing sem for better performance fixed for 3.0.y
Fix GCC 4.8.x
add exynos-rng and fix compilation errors