installer: accept WPA passphrases up to 50 chars.

installer.sh.in

@@ -472,7 +472,7 @@ configure_wifi() {
     DIALOG --form "Wireless configuration for ${dev}\n(encryption type: wep or wpa)" 0 0 0 \
         "SSID:" 1 1 "" 1 16 30 0 \
         "Encryption:" 2 1 "" 2 16 3 0 \
-        "Password:" 3 1 "" 3 16 30 0 || return 1
+        "Password:" 3 1 "" 3 16 50 0 || return 1
     set -- $(cat $ANSWER)
     ssid="$1"; enc="$2"; pass="$3";