EDAC/igen6: Fix call trace due to missing release()

EDAC/igen6: Fix call trace due to missing release()

When unloading the igen6_edac driver, there is a call trace:

  Device '(null)' does not have a release() function, it is broken and must be fixed.
  See Documentation/core-api/kobject.rst.
  WARNING: drivers/base/core.c:2567 at device_release+0x84/0x90, CPU#5: rmmod/127209
  ...
  RIP: 0010:device_release+0x84/0x90
  Call Trace:
   <TASK>
   kobject_put+0x8c/0x220
   put_device+0x17/0x30
   igen6_unregister_mcis+0xa2/0xe0 [igen6_edac]
   igen6_remove+0x82/0xb0 [igen6_edac]
   ...

Fix the call trace by providing empty release() functions for the
memory controller devices.

Fixes: 10590a9d4f23 ("EDAC/igen6: Add EDAC driver for Intel client SoCs using IBECC")
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20260403054029.3950383-2-qiuxu.zhuo@intel.com