Ignore invalid nbstates

Author: AYuusuke

amdctl.c

@@ -745,6 +745,7 @@ void printNbStates() {
 			const uint32_t addresses[][4] = {{0x160, 0x164, 0x168, 0x16c}};
 			for (int nbpstate = 0; nbpstate < nbpstates; nbpstate++) {
 				rwPciReg("18.5", addresses[0][nbpstate], 1);
+				if (!getDec("0:0")) continue;
 				nbvid = ((getDec("16:10") + (getDec("21:21") << 7)));
 				nbfid = getDec("7:7");
 				nbdid = getDec("6:1");