Not handling wrong CRC

[TK-A369]

lidar-avr/lidar-avr.c

Lines 107 to 115 in 30be813

	if (frame_ready && crc == frame[FRAME_SERVO_LEN - 1]) {
	byte_number = 0;
	frame_ready = 0;
	uint16_t pwm = (frame[4] << 8) + frame[5];
	if (pwm >= MIN_DUTY && pwm <= MAX_DUTY) {
	OCR1A = pwm; // Set PWM TOP to received PWM duty
	}
	frame_ready = 0;
	}

If CRC is correct, program sets servo and clears frame_ready. And in this case it works.
But if CRC is wrong, program won't enter to if, and frame_ready won't be cleared.
So program can hang when CRC will be wrong. It should be changed. If frame_ready is 1, but CRC is wrong, ignore this frame, and maybe send info about CRC error.