ethtool: eeprom: add missing ethnl_ops_begin() / _complete() during fallback

ethtool: eeprom: add missing ethnl_ops_begin() / _complete() during fallback

All ethtool driver op calls should be sandwiched between
ethnl_ops_begin() / ethnl_ops_complete(). In Netlink eeprom code,
if the paged access failed we fall back to old API, but we
first call _complete() and the fallback never does its own
ethnl_ops_begin(). Move the fallback into the _begin() / _complete()
section.

Fixes: 96d971e307cc ("ethtool: Add fallback to get_module_eeprom from netlink command")
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/20260526153533.2779187-10-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>