Revert "cpu: Move cpu_common_props to hw/core/cpu.c"

This reverts commit 1b36e4f5a5.

Despite a comment saying why cpu_common_props cannot be placed in
a file that is compiled once, it was moved anyway.  Revert that.

Since then, Property is not defined in hw/core/cpu.h, so it is now
easier to declare a function to install the properties rather than
the Property array itself.

Cc: Eduardo Habkost <ehabkost@redhat.com>
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

cpu.c

@@ -179,6 +179,27 @@ void cpu_exec_unrealizefn(CPUState *cpu)
     cpu_list_remove(cpu);
 }
 
+static Property cpu_common_props[] = {
+#ifndef CONFIG_USER_ONLY
+    /*
+     * Create a memory property for softmmu CPU object,
+     * so users can wire up its memory. (This can't go in hw/core/cpu.c
+     * because that file is compiled only once for both user-mode
+     * and system builds.) The default if no link is set up is to use
+     * the system address space.
+     */
+    DEFINE_PROP_LINK("memory", CPUState, memory, TYPE_MEMORY_REGION,
+                     MemoryRegion *),
+#endif
+    DEFINE_PROP_BOOL("start-powered-off", CPUState, start_powered_off, false),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+void cpu_class_init_props(DeviceClass *dc)
+{
+    device_class_set_props(dc, cpu_common_props);
+}
+
 void cpu_exec_initfn(CPUState *cpu)
 {
     cpu->as = NULL;