fixed potentially illegal branches

c64/kernal/f34a.open.s

@@ -21,7 +21,9 @@ open:
 	dey
 	lda LAT, y
 	cmp current_logical_filenum
-	beq kernalerror_FILE_ALREADY_OPEN
+	bne open_not_yet_open
+	jmp kernalerror_FILE_ALREADY_OPEN
+open_not_yet_open:
 	cpy #$00
 	jmp -
 *

c64/kernal/iec/iec_tx_byte.s

@@ -90,6 +90,7 @@ iec_tx_common_bit_is_sent:
 	bpl +
 	dex
 	bne -
-	bpl iec_return_DEVICE_NOT_FOUND
+	bmi +
+	jmp iec_return_DEVICE_NOT_FOUND
 *
 	jmp iec_return_success