[klibc] Massive code drop

[H. Peter Anvin]

I have released a patch for klibc which changes off_t to 64 bits, and 
hopefully deals with most of the rest of the fallout.  We shouldn't be 
using any obsolescent types anymore, except for struct statfs (I intend 
to hack that next so we use statfs64() and fstatfs64()).  We're still 
using some older system calls, like sigaction() instead of 
rt_sigaction() where available, but that's a pure convenience.

	-hpa