regedit: Check that we were able to allocate line_buf too.

programs/regedit/regproc.c

@@ -1241,7 +1241,7 @@ BOOL export_registry_key(WCHAR *file_name, WCHAR *reg_key_name, DWORD format)
                              val_name_len * sizeof(*val_name_buf));
     val_buf = HeapAlloc(GetProcessHeap(), 0, val_size);
     line_buf = HeapAlloc(GetProcessHeap(), 0, line_buf_size);
-    CHECK_ENOUGH_MEMORY(reg_key_name_buf && val_name_buf && val_buf);
+    CHECK_ENOUGH_MEMORY(reg_key_name_buf && val_name_buf && val_buf && line_buf);
 
     if (reg_key_name && reg_key_name[0]) {
         HKEY reg_key_class;