这个esb_ll文件中3个函数找不到，编译时有警告，需要理会吗，怎么消除警告

we_4558502706

../esb_ll/esb_ll.c: In function 'ESB_GetAddress':
../esb_ll/esb_ll.c:369:10: warning: implicit declaration of function 'multi_byte_reg_read'
../esb_ll/esb_ll.c: In function 'ESB_SetTxMI':
../esb_ll/esb_ll.c:1059:2: warning: implicit declaration of function 'rf_set_tx_modulation_index'
../esb_ll/esb_ll.c: In function 'ESB_SetRxMI':
../esb_ll/esb_ll.c:1070:2: warning: implicit declaration of function 'rf_set_rx_modulation_index'