man: explicitly use format_up/format_down in ethernet, wireless conf
man: explicitly use format_up/format_down in ethernet, wireless conf

Clearly indicate format_up and format_down are used for configuring ethernet
and wireless sections instead of format.

Signed-off-by: Tomas Krizek <41599d6915268be5f6206f953e5faed075f2bebf@mailbox.org>

i3/i3status,Gravemind/i3status,Dettorer/i3status,lexszero/i3status,i3/i3status,Gravemind/i3status,Dettorer/i3status,peder2tm/i3status-netdev,Dettorer/i3status,lexszero/i3status,peder2tm/i3status-netdev,Gravemind/i3status,Dettorer/i3status,i3/i3status,lexszero/i3status,i3/i3status,peder2tm/i3status-netdev,lexszero/i3status,peder2tm/i3status-netdev,Gravemind/i3status