wifi_statistics: Return a more accurate error

Signed-off-by: Jonathan Bither <jonbither@gmail.com>
wifi_statistics: Fix double usage of variable 'rcu'

Signed-off-by: Jonathan Bither <jonbither@gmail.com>
wifi_statistics: Add missing newlines for mode output

Signed-off-by: Jonathan Bither <jonbither@gmail.com>
wifi_statistics: Cleanup JSON formatting when there are multiple seqnos

Signed-off-by: Jonathan Bither <jonbither@gmail.com>
wifi_statistics: Use eth_zero_addr() instead of memset

Signed-off-by: Jonathan Bither <jonbither@gmail.com>