Update download URLs for some systems - it seems like Lenovo has been shuffling things around

docs/firmware_download.txt

@@ -10,17 +10,17 @@ bootable BIOS update CD images for both the current and historical releases.
 e220    https://support.lenovo.com/hk/en/downloads/DS031908
 l430    https://support.lenovo.com/hk/en/downloads/DS018887
 p51     https://support.lenovo.com/hk/en/downloads/DS121297
-t430    https://support.lenovo.com/hk/en/downloads/DS029253
-t430s   https://support.lenovo.com/au/en/downloads/ds029725
+t430    https://pcsupport.lenovo.com/gb/en/downloads/DS029252
+t430s   https://pcsupport.lenovo.com/gb/en/downloads/DS029724
 t470    https://support.lenovo.com/hk/en/downloads/DS120430
 t470p   https://support.lenovo.com/hk/en/downloads/DS120708
 t480    https://support.lenovo.com/hk/en/downloads/DS502357
-t530    https://support.lenovo.com/hk/en/downloads/DS029249
-w530    https://support.lenovo.com/hk/en/downloads/DS029170
+t530    https://pcsupport.lenovo.com/gb/en/downloads/DS029246
+w530    https://pcsupport.lenovo.com/gb/en/downloads/DS029169
 x131e   https://support.lenovo.com/au/en/downloads/ds029773
 x220    https://support.lenovo.com/hk/en/downloads/DS018807
 x230    https://pcsupport.lenovo.com/hk/en/downloads/DS029187
-x230t   https://support.lenovo.com/hk/en/downloads/DS018887
+x230t   https://pcsupport.lenovo.com/gb/en/downloads/DS029683
 x240    https://support.lenovo.com/hk/en/downloads/DS035952
 x250    https://pcsupport.lenovo.com/au/en/downloads/ds102289
 x260    https://support.lenovo.com/hk/en/downloads/DS105891