cpu: Change cpu_exit() argument to CPUState

It no longer depends on CPUArchState, so move it to qom/cpu.c.

Prepares for changing GDBState::c_cpu to CPUState.

Signed-off-by: Andreas Färber <afaerber@suse.de>
diff --git a/qom/cpu.c b/qom/cpu.c
index dba4a11..8a122b0 100644
--- a/qom/cpu.c
+++ b/qom/cpu.c
@@ -91,6 +91,12 @@
     cpu->interrupt_request &= ~mask;
 }
 
+void cpu_exit(CPUState *cpu)
+{
+    cpu->exit_request = 1;
+    cpu->tcg_exit_req = 1;
+}
+
 int cpu_write_elf32_qemunote(WriteCoreDumpFunction f, CPUState *cpu,
                              void *opaque)
 {