betransform: Do not try to transform Copy nodes.

There are no Copy nodes in the backend this early.
ia32: Remove pointless test.

An ia32 Load always loads into a GP register.
ia32: Simplify test, whether a Copy copies a GP value.
be: Use out registers instead of in register, when possible.

It is more consistent to use them and they are slightly faster to fetch.
belower: Remove the unused attribute irg from struct lower_env_t.
be: Constify array parameters.
be: Dump register assignments at the inputs of nodes.
be: Do not dump the input node, only the slot, for "should be same" and "must be different" constraints.

The node in question is shown just a few lines above and repeating it here just clutters up the info box.
cleanup: Remove unnecessary #include <string.h>.
cleanup: Remove unnecessary #include <stddef.h>.
cleanup: Remove pointless assert().
cleanup: Remove unnecessary #include <assert.h>.
Remove unnecessary #include "bearch_arm_t.h".
cleanup: Remove unnecessary #include "bearch_ia32_t.h".
cleanup: Remove unnecessary #include "irgraph.h".
cleanup: Include "irgraph_t.h" instead of "irgraph.h" internally.
belower: Simplify lower_perm_node().
ia32_finish: use C99 features
include util.h instead of adt/util.h
Makefile: use ir subdirs instead of enumerating them manually