base & x86: setup GOT pointer in crt0.s

This is normally needed in LDSO and was previously done by the LDSO specific crt0.s.
I forgot to keep it during the unification of the different crt0s.

fix #1077
ldso: Export HW system call interface

Fixes #1081
hw: disable assertions if release spec is set only

Fix #1071
hw: remove use of float in exynos timer (fix #713)
fiasco.oc: remove redundant atomic.h header

Fixes #565
base-hw: reenable failsafe run script (Fix #801)
hw: simplify Page_flags (fix #711)

Instead of using a special bitfield use a compound of boolean
values for the generic page attributes. To reduce copy overhead,
change the corresponding functions, where Page_flags are used as
arguments, to use references.
gdb_monitor: improve the backtrace test

With this patch, functions which execute blocking syscalls on Fiasco.OC
are built with frame pointers to get a correct backtrace shown in GDB.

Also, the backtrace test for a thread currently executing a syscall now
traces the  'Genode::Thread_base::join()' function instead of
'Genode::sleep_forever()', because base-nova has a custom implementation
of 'Genode::sleep_forever()' with a different backtrace than on Fiasco.OC.

Fixes #1061.
mmio: provide bits method for bitsets

ref #1006
Clarify comment
mmio: provide set and get method for bitsets

ref #1006
hw & arm: simplify TLB permission bits via bitsets

ref #1006
hw & arm: simplify TLB descriptor-type bits

ref #1006
hw & arm_v7: clean up TLB driver

ref #1006
hw & arm_v6: clean up TLB driver

ref #1006
hw & arm: declare every mapping as MP shared

ref #1006
hw: kernel initialization in extra function

ref #1006
hw: fix assembly alignments

ref #1006
hw & arm: clean up core CRT0

ref #1006
hw_arndale: idle threads on secondary processors

fix #1006