kunit: Export kunit_running()

Using kunit_fail_current_test() in a loadable module causes a link
error like:

ERROR: modpost: "kunit_running" [drivers/gpu/drm/vc4/vc4.ko] undefined!

Export the symbol to allow using it from modules.

Fixes: da43ff045c ("drm/vc4: tests: Fail the current test if we access a register")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

lib/kunit/test.c

@@ -21,6 +21,7 @@
 #include "try-catch-impl.h"
 
 DEFINE_STATIC_KEY_FALSE(kunit_running);
+EXPORT_SYMBOL_GPL(kunit_running);
 
 #if IS_BUILTIN(CONFIG_KUNIT)
 /*