We never used the distinction which flags get modified, so just simplify the specification a bit.

Handle this similar to the ia32 backend.

We can easily identify the outputs producing a stack pointer by looking
if the stack pointer register is assigned. Unfortunately this also
needed a new mechanism to tell the verifier that some registers are not
in SSA form (all the time) which needs a few extra lines in each
backend.

amd64, arm, sparc: Replace the dependency edge of the IncSP after the Call by a stack output of the call.

This removes the only uses of dependency edges.

* Use rbp and rsp as output of leave, not rbp twice.
* Attach the rbp input/output of leave to rbp, not rsp.
* Use the function's own frame pointer instead of the caller's frame pointer.

Directly use in_reqs => [ ... ], out_reqs => [ ... ].

This first version should perform similar to the support in the ia32
backend, but needs more work to add amd64 specific immediate types.

This is in preparation for a removal of the generic arch_irn_flag_modify_flags

This should fix firm-testsuite/fehler242.c