Add clone in x86

clone is already declared in header and exists in both arm/mips libc.
Add the missing one in libc.so and libc.a (*1) for x86.

(*) only updated bionic_clone.o and clone.o from build after
22d366cc09383956dc264ed4641572e609392eee

Change-Id: Ibcb39948d48b84398543d84304ead21dab534c40
2 files changed