Description:
------------
Today after my weekly upgrading arch, see this message at the end of it :
==> Unable to install module broadcom-wl/6.30.223.271 for kernel 4.18.6-arch1-1-ARCH: Missing kernel modules tree.

Additional info:
* package version(s)
* config and/or log files etc.

list of concerned packages :
--------------------------
Paquets (101) attica-5.50.0-1 baloo-5.50.0-1 bluez-qt-5.50.0-1 breeze-icons-5.50.0-1 brltty-5.6-4 curl-7.61.1-1 dolphin-18.08.1-2 dotconf-1.3-5 dragon-18.08.1-2
extra-cmake-modules-5.50.0-1 frameworkintegration-5.50.0-1 glib2-2.58.0-1 glib2-docs-2.58.0-1 gwenview-18.08.1-2 json-c-0.13.1-2 juk-18.08.1-2
kactivities-5.50.0-1 kactivities-stats-5.50.0-1 karchive-5.50.0-1 kauth-5.50.0-1 kbookmarks-5.50.0-1 kcmutils-5.50.0-1 kcodecs-5.50.0-1
kcompletion-5.50.0-1 kconfig-5.50.0-1 kconfigwidgets-5.50.0-1 kcoreaddons-5.50.0-1 kcrash-5.50.0-1 kdbusaddons-5.50.0-1
kde-syndication-18.08.1-1 [suppression] kdeclarative-5.50.0-1 kded-5.50.0-1 kdelibs4support-5.50.0-1 kdesu-5.50.0-1 kdnssd-5.50.0-1 kdoctools-5.50.0-1
kemoticons-5.50.0-1 kfilemetadata-5.50.0-1 kglobalaccel-5.50.0-1 kguiaddons-5.50.0-1 kholidays-1:5.50.0-1 khtml-5.50.0-1 ki18n-5.50.0-1
kiconthemes-5.50.0-1 kidletime-5.50.0-1 kinit-5.50.0-1 kio-5.50.0-1 kio-extras-18.08.1-2 kirigami2-5.50.0-1 kitemmodels-5.50.0-1 kitemviews-5.50.0-1
kjobwidgets-5.50.0-1 kjs-5.50.0-1 kjsembed-5.50.0-1 klettres-18.08.1-2 kmousetool-18.08.1-2 knewstuff-5.50.0-1 knotifications-5.50.0-1
knotifyconfig-5.50.0-1 kpackage-5.50.0-1 kparts-5.50.0-1 kpeople-5.50.0-1 kplotting-5.50.0-1 kpty-5.50.0-1 kross-5.50.0-1 krunner-5.50.0-1
kservice-5.50.0-1 ksirk-18.08.1-2 ktexteditor-5.50.0-1 ktextwidgets-5.50.0-1 kunitconversion-5.50.0-1 kwallet-5.50.0-1 kwayland-5.50.0-1
kwidgetsaddons-5.50.0-1 kwin-5.13.5-2 kwindowsystem-5.50.0-1 kxmlgui-5.50.0-1 kxmlrpcclient-5.50.0-1 libao-1.2.2-2 libarchive-3.3.3-1 libspeechd-0.8.8-2
linux-headers-4.18.6.arch1-1 mailcommon-18.08.1-2 mesa-18.1.8-1 modemmanager-qt-5.50.0-1 networkmanager-qt-5.50.0-1 okular-18.08.1-3
plasma-framework-5.50.0-1 polkit-0.115+3+g8638ec5-1 prison-5.50.0-1 purpose-5.50.0-1 python-atspi-2.26.0-3 qqc2-desktop-style-5.50.0-1 qt5-location-5.11.1-3
solid-5.50.0-1 sonnet-5.50.0-1 speech-dispatcher-0.8.8-2 syndication-5.50.0-1 syntax-highlighting-5.50.0-1 threadweaver-5.50.0-1 orca-3.28.1-2


Steps to reproduce:
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having macbook air with arch on it, or wifi broadcom ?
Don't know what to add here.