(bug 48404) Update fdcwiki and ombudsmenwiki favicons

This commit changes the fdcwiki and ombudsmenwiki favicons
from, respectively, the Wikipedia and Meta favicons into the
general Wikimedia favicon per bug 48379, comment 1 and
bug 48379, comment 4.

I also used the opportunity to fix some weird spacing in
other $wgFavicon definitions.

Bug: 48404
Change-Id: Ic9dd8b65f95034ff50fe9608e89405dacbd3c654