net/core: Make use of assign_bit() API

We have for some time the assign_bit() API to replace open coded

	if (foo)
		set_bit(n, bar);
	else
		clear_bit(n, bar);

Use this API in the code. No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Message-ID: <20230710100830.89936-1-andriy.shevchenko@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>