Added dynamic linking support for x86_64.
Fixes for eco32 and mmix.
Use the C++ functions of Cache in C++-code.
Removed unnecessary A_UNUSED.
crt0.S: more consistency.
Separated TLS stuff from initialization.
Fixed reboot/shutdown screen.
Increased the kernel-heap-size.
Increase the number of kframes at runtime, if necessary.
Fixed segment-registers for SMP.
init: increased max-wait time for devices.

For example, in bochs x86emu takes quite long, so that
we timed out there.