setupapi: Avoid NULL dereference in error path (Coverity).
diff --git a/dlls/setupapi/parser.c b/dlls/setupapi/parser.c
index 7f581bd..744ee4c 100644
--- a/dlls/setupapi/parser.c
+++ b/dlls/setupapi/parser.c
@@ -1024,7 +1024,7 @@
     UnmapViewOfFile( buffer );
     if (err)
     {
-        free_inf_file( file );
+        if (file) free_inf_file( file );
         SetLastError( err );
         file = NULL;
     }