Linux: Consolidate typesizes.h

The generic (sysdeps/unix/sysv/linux/generic/bits/typesizes.h) and
default (bits/typesizes.h) differs in two fields:

                    bits/typesizes.h    Linux generic
__NLINK_T_TYPE      __UWORD_TYPE        __U32_TYPE
__BLKSIZE_T_TYPE    __SLONGWORD_TYPE    __S32_TYPE

Sinceit leads to different C++ mangling names, the default typesize.h
is copied for the requires archtiectures and the generic is make the
default Linux one.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>