Set LOGBUFSIZE to 8192 on RP2040_Audio target

Do this the right way :)

platformio.ini

@@ -107,6 +107,7 @@ extends = env:ZuluSCSI_RP2040
 build_flags =
     ${env:ZuluSCSI_RP2040.build_flags}
     -DENABLE_AUDIO_OUTPUT
+    -DLOGBUFSIZE=8192
 
 ; Variant of RP2040 platform, based on Raspberry Pico board and a carrier PCB
 ; Differs in pinout from ZuluSCSI_RP2040 platform, but shares most of the code.