[klibc] klibc and clone()

[H. Peter Anvin]

OK, I have added the following builtins to klibc:

	__clone(flags, sp)

and on IA64:

	__clone2(flags, sp, rsp)

HOWEVER, these are really not useful to call if sp != NULL, so it's really:

	__clone(flags, NULL)

Since this is the only use supported, I have added an inline for IA64 which 
calls __clone2() if the user calls __clone().

Note that this is different from the glibc clone()/clone2() wrappers.

	-hpa