Move cpu_exec_init_all() declaration to qemu-common.h

Let cpu_exec_init_all() be called from non-CPU code.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/qemu-common.h b/qemu-common.h
index 087c034..d881a39 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -231,6 +231,8 @@
 
 typedef uint64_t pcibus_t;
 
+void cpu_exec_init_all(unsigned long tb_size);
+
 /* CPU save/load.  */
 void cpu_save(QEMUFile *f, void *opaque);
 int cpu_load(QEMUFile *f, void *opaque, int version_id);