[PATCH] kunit: platform: Resolve 'struct completion' warning

[Brian Norris <briannorris@xxxxxxxxxxxx>]

If the <kunit/platform_device.h> header is included in a test without
certain other headers, it produces compiler warnings like:

In file included from [...]
../include/kunit/platform_device.h:15:57: warning: ‘struct completion’
declared inside parameter list will not be visible outside of this
definition or declaration
   15 |                                                  struct completion *x);
      |                                                         ^~~~~~~~~~

Add a 'struct completion' forward declaration to resolve this.

Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
---
I'm not bothering with a Fixes tag, since this only shows up with new
tests I'm writing.

 include/kunit/platform_device.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/kunit/platform_device.h b/include/kunit/platform_device.h
index 0fc0999d2420..f8236a8536f7 100644
--- a/include/kunit/platform_device.h
+++ b/include/kunit/platform_device.h
@@ -2,6 +2,7 @@
 #ifndef _KUNIT_PLATFORM_DRIVER_H
 #define _KUNIT_PLATFORM_DRIVER_H
 
+struct completion;
 struct kunit;
 struct platform_device;
 struct platform_driver;
-- 
2.47.1.613.gc27f4b7a9f-goog