swupdate.inc: add OFL-1.1 to LICENSE:${PN}-www
The www sub-package ships Font Awesome fonts
(examples/www/v2/webfonts/fa-solid-900.{ttf,woff2}) which are
licensed under SIL OFL 1.1. LICENSES/OFL-1.1.txt is already present
in the source tree and referenced in LIC_FILES_CHKSUM, but
LICENSE:${PN}-www only declared MIT, omitting OFL-1.1.
Signed-off-by: Hamish Guthrie <hamish.guthrie@kistler.com>