Thanks, I’ll have a look at that one.
edit
Got it working 
resolving dependencies...
looking for conflicting packages...
Packages (1) ryzen_smu-dkms-git-67.46daaef-1
Total Installed Size: 0,24 MiB
:: Proceed with installation? [Y/n]
(1/1) checking keys in keyring [########################################################] 100%
(1/1) checking package integrity [########################################################] 100%
(1/1) loading package files [########################################################] 100%
(1/1) checking for file conflicts [########################################################] 100%
(1/1) checking available disk space [########################################################] 100%
:: Processing package changes...
(1/1) installing ryzen_smu-dkms-git [########################################################] 100%
:: Running post-transaction hooks...
(1/2) Arming ConditionNeedsUpdate...
(2/2) Install DKMS modules
==> dkms install --no-depmod -m ryzen_smu -v 67.46daaef -k 5.9.0-1-MANJARO
==> dkms install --no-depmod -m ryzen_smu -v 67.46daaef -k 5.8.13-3-MANJARO
==> dkms install --no-depmod -m ryzen_smu -v 67.46daaef -k 5.7.19-2-MANJARO
==> depmod 5.9.0-1-MANJARO
==> depmod 5.7.19-2-MANJARO
==> depmod 5.8.13-3-MANJARO
PKGBUILD
_pkgbase=ryzen_smu
pkgname=ryzen_smu-dkms-git
pkgver=67.46daaef
pkgrel=1
pkgdesc="A Linux kernel driver that exposes access to the SMU (System Management Unit) for certain AMD Ryzen Processors"
arch=('x86_64')
url="https://gitlab.com/leogx9r/ryzen_smu"
license=('GPL2')
depends=('dkms')
makedepends=('git' 'linux-headers')
provides=('ryzen_smu')
source=("$_pkgbase::git+$url.git"
"dkms.conf"
"$_pkgbase.conf")
sha256sums=('SKIP'
'0ced27963dac8e270221574d0c2b686bbbb012e3af8741188800f9cb6b7d8e63'
'a48f5c846ca5fd8f185f1317c8001c97f59ac432392d53b581802c7761b9360f')
pkgver() {
cd "$srcdir/$_pkgbase"
printf "%s.%s" "$(git rev-list --count HEAD)" "$(git rev-parse --short HEAD)"
}
package() {
cd "$srcdir/$_pkgbase"
install -d "${pkgdir}"/usr/src/${_pkgbase}-${pkgver}/
cp -r ${srcdir}/${_pkgbase}/* "${pkgdir}"/usr/src/${_pkgbase}-${pkgver}/
install -Dm644 ${srcdir}/dkms.conf "${pkgdir}"/usr/src/${_pkgbase}-${pkgver}/dkms.conf
sed -e "s/@_PKGBASE@/${_pkgbase}/" \
-e "s/@PKGVER@/${pkgver}/" \
-i "${pkgdir}"/usr/src/${_pkgbase}-${pkgver}/dkms.conf
install -Dm644 ${srcdir}/${_pkgbase}.conf "${pkgdir}"/usr/lib/depmod.d/${_pkgbase}.conf
}
dkms.conf
PACKAGE_NAME="@_PKGBASE@"
PACKAGE_VERSION="@PKGVER@"
MAKE[0]="make -C $kernel_source_dir M=$dkms_tree/$PACKAGE_NAME/$PACKAGE_VERSION/build modules"
CLEAN="make clean"
BUILT_MODULE_NAME[0]="@_PKGBASE@"
DEST_MODULE_LOCATION[0]="/kernel/drivers/@_PKGBASE@"
AUTOINSTALL="yes"
ryzen_smu.conf
#
# /usr/lib/depmod.d/ryzen_smu.conf
#
search updates extramodules built-in
Thanks again for the hint @Yochanan