rrm: include actual parent TSF value

If the scan results included a parent TSF value use it.

src/rrm.c

@@ -270,8 +270,13 @@ static size_t build_report_for_bss(struct rrm_beacon_req_info *beacon,
 	to += 6;
 	/* Antenna identifier unknown */
 	*to++ = 0;
-	/* Parent TSF - zero */
-	memset(to, 0, 4);
+	/*
+	 * 802.11 9.4.2.22.7 Beacon report
+	 *
+	 * "The Parent TSF field contains the lower 4 octets of the measuring
+	 *  STA’s TSF timer value"
+	 */
+	l_put_le32((uint32_t)(bss->parent_tsf & 0xffffffff), to);
 	to += 4;
 
 	/*