Sabre Wulf: Routine at BF17

BF17: Routine at BF17

Used by the routines at 9E72, AAED and AD69.
BF17	LD C,$30	C=30.
BF19	LD A,C
BF1A	OR %00011000	Set bits 3-4.
BF1C	DAA
BF1D	LD B,A
BF1E	CALL PlaySquareWave	Call PlaySquareWave.
BF21	DEC C
BF22	JR NZ,$BF19
BF24	RET	Return.