um: Remove double zero check

free_pages() performs a parameter null check inside
therefore remove double zero check here.

Signed-off-by: Shaojie Dong <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Johannes Berg <[email protected]>

Author: Shaojie Dong

arch/um/kernel/skas/mmu.c

@@ -46,8 +46,7 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm)
 	return 0;
 
  out_free:
-	if (new_id->stack != 0)
-		free_pages(new_id->stack, ilog2(STUB_DATA_PAGES));
+	free_pages(new_id->stack, ilog2(STUB_DATA_PAGES));
  out:
 	return ret;
 }