fix: serve dolphin's PAL IPL for australia

Dolphin files the Australian country code under Region::PAL, whose
IPL lives in GC/EUR. Tagged europe alone, --region australia dropped
it and kept the American IPL, which Dolphin never reads for those
discs.

emulators/primehack.yml

@@ -43,7 +43,7 @@ files:
 
   - name: "IPL.bin"
     path: "GC/EUR/IPL.bin"
-    region: [europe]
+    region: [europe, oceania]
     size: 2097152
     required: false
     hle_fallback: true