net: dsa: vsc73xx: fix possible subblocks range of CAPT block

CAPT block (CPU Capture Buffer) have 7 sublocks: 0-3, 4, 6, 7.
Function 'vsc73xx_is_addr_valid' allows to use only block 0 at this
moment.

This patch fix it.

Fixes: 05bd97fc ("net: dsa: Add Vitesse VSC73xx DSA router driver")
Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20240903203340.1518789-1-paweldembicki@gmail.com


Signed-off-by: Paolo Abeni <pabeni@redhat.com>