[RPi4-bcmgenet] regression: EEE reporting/dtparam support broken (EEE always enabled)

### Describe the bug Just noticed some link stability issues and huge lags today while using SSH to some of my Pi 4. Turned out `dmesg` is showing recurrent network link resets: ``` [...] [ 9.208361] bcmgenet fd580000.ethernet: configuring instance for external RGMII (RX delay) [ 9.211047] bcmgenet fd580000.ethernet eth0: Link is Down [ 13.309882] bcmgenet fd580000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx [ 120.829975] bcmgenet fd580000.ethernet eth0: Link is Down [ 122.878105] bcmgenet fd580000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx [ 255.999156] bcmgenet fd580000.ethernet eth0: Link is Down [ 259.071376] bcmgenet fd580000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx [ 283.647776] bcmgenet fd580000.ethernet eth0: Link is Down [ 286.720047] bcmgenet fd580000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx [ 301.056130] bcmgenet fd580000.ethernet eth0: Link is Down [ 304.128371] bcmgenet fd580000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx [...] ``` Not 100% sure if this is due to a recent kernel update, or a recent eeprom update. It looks like the `cmdline.txt` option `dtparam=eee=off` has no effect anymore, and `ethtool --show-eee eth0` indicates there is no more ability to report EEE status: ``` EEE settings for eth0: EEE status: not supported ``` Strangely enough however, on Pi 3 B+ the `ethtool --show-eee eth0` is still working. Also, playing `ethtool --set-eee eth0 eee off` still seems to successfully disable EEE on Pi 4 despite being unable to report EEE status. Thanks in advance if this can be fixed (at least for the dtparam option) ### Steps to reproduce the behaviour Connect a recently updated Pi 4 to a GigE device (computer or switch) which supports EEE, and during low network activity, link stability issues are likely to occur, despite `cmdline.txt` containing `dtparam=eee=off`. The `ethtool --show-eee eth0` and `ethtool --set-eee eth0 eee off` effect may also be tested. ### Device (s) Raspberry Pi 4 Mod. B ### System raspinfo: https://pastebin.com/LL09cwJS Output of `cat /etc/rpi-issue`: ``` Raspberry Pi reference 2025-10-01 Generated using pi-gen, https://github.com/RPi-Distro/pi-gen, 7dadcf1fc5ce1648ab09409ab978831690c9a955, stage2 ``` Output of `vcgencmd version`: ``` May 8 2026 18:13:05 Copyright (c) 2012 Broadcom version ae9a8ea9f3ca745de6f357bd7fc8307721ad38b7 (clean) (release) (start) ``` Output of `uname -a`: `Linux pi4-spycrobe 6.18.29+rpt-rpi-v8 #1 SMP PREEMPT Debian 1:6.18.29-1+rpt1 (2026-05-12) aarch64 GNU/Linux` ### Logs [dmesg.txt](https://github.com/user-attachments/files/27803244/dmesg.txt) ### Additional context _No response_