fix: set auth_mode=open for RADIUS splash page on EQT-CORPO SSID

open-with-radius es para MAC-based RADIUS (sin splash), incompatible
con splash pages. auth_mode=open con custom RADIUS splash es la
combinacion correcta para captive portal + autenticacion RADIUS.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

sites/bcn01/ssids.auto.tfvars

@@ -7,9 +7,8 @@ wireless_ssids = [
     number              = 0
     name                = "EQT-CORPO"
     enabled             = true
-    auth_mode           = "open-with-radius"
+    auth_mode           = "open"
     splash_page         = "Password-protected with custom RADIUS"
-    wpa_encryption_mode = "WPA3 only"
     ip_assignment_mode  = "Bridge mode"
     use_vlan_tagging    = true
     default_vlan_id     = 100