doc: Correct typo in comment.

ir/be/bearch.h

@@ -122,7 +122,7 @@ static inline void arch_add_irn_flags(ir_node *const node, arch_irn_flags_t cons
 
 /**
  * Returns true if the given node should not be scheduled (has
- * arch_irn_flag_not_scheduled flag seet)
+ * arch_irn_flag_not_scheduled flag set)
  */
 static inline bool arch_is_irn_not_scheduled(const ir_node *node)
 {