[PATCH-for-8.0] coroutine: Add missing <qemu/atomic.h> include

[Philippe Mathieu-Daudé]

qemu_co_mutex_assert_locked() calls qatomic_read(), which
is declared in <qemu/atomic.h>. This fixes when refactoring:

  In file included from include/qemu/osdep.h:113,
                   from ../../util/error-report.c:13:
  include/qemu/coroutine.h: In function 'qemu_co_mutex_assert_locked':
  include/qemu/coroutine.h:182:12: error: implicit declaration of function 
'qatomic_read' [-Werror=implicit-function-declaration]
    182 |     assert(qatomic_read(&mutex->locked) &&
        |            ^~~~~~~~~~~~

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 include/qemu/coroutine.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/qemu/coroutine.h b/include/qemu/coroutine.h
index 89650a2d7f..1750c30d8e 100644
--- a/include/qemu/coroutine.h
+++ b/include/qemu/coroutine.h
@@ -17,6 +17,7 @@
 
 #include "qemu/queue.h"
 #include "qemu/timer.h"
+#include "qemu/atomic.h"
 
 /**
  * Coroutines are a mechanism for stack switching and can be used for
-- 
2.38.1