net: Remove shadow variable in netdev_run_todo()

Fix a shadow variable warning in net/core/dev.c when compiled with
CONFIG_LOCKDEP enabled. The warning occurs because 'dev' is redeclared
inside the while loop, shadowing the outer scope declaration.

	net/core/dev.c:11211:22: warning: declaration shadows a local variable [-Wshadow]
		struct net_device *dev = list_first_entry(&unlink_list,

	net/core/dev.c:11202:21: note: previous declaration is here
		struct net_device *dev, *tmp;

Remove the redundant declaration since the variable is already defined
in the outer scope and will be overwritten in the subsequent
list_for_each_entry_safe() loop anyway.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250221-netcons_fix_shadow-v1-1-dee20c8658dd@debian.org


Signed-off-by: Jakub Kicinski <kuba@kernel.org>