include/uapi/linux/patchkey.h: change #error to #warning if file included directly

Would be nice to be able to compile all userspace header files also alone.

Signed-off-by: Mikko Rapeli <redacted>
---
 include/uapi/linux/patchkey.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/linux/patchkey.h b/include/uapi/linux/patchkey.h
index 1bda0e5..cee195d 100644
--- a/include/uapi/linux/patchkey.h
+++ b/include/uapi/linux/patchkey.h

@@ -11,7 +11,7 @@
  */
 
 #ifndef _LINUX_PATCHKEY_H_INDIRECT
-#error "patchkey.h included directly"
+#warning "patchkey.h included directly"
 #endif
 
 #ifndef _UAPI_LINUX_PATCHKEY_H

-- 
2.1.4