remove unused files

There are several unused files, primarily because powerpc is an unused
arch. The exceptions are config-ia64.mak, which is also an unused arch
file, lib/fwcfg.c, lib/panic.c, x86/print.h and x86/run-kvm-unit-tests,
which are just unused. Remove them all in order to tidy things up.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>