protobuf-c from home:portalofreedom project

For Fedora 41 run the following as root:

dnf config-manager addrepo --from-repofile=https://download.opensuse.org/repositories/home:portalofreedom/Fedora_41/home:portalofreedom.repo
dnf install protobuf-c

For openSUSE Tumbleweed run the following as root:

zypper addrepo https://download.opensuse.org/repositories/home:portalofreedom/openSUSE_Tumbleweed/home:portalofreedom.repo
zypper refresh
zypper install protobuf-c

For 15.6 run the following as root:

zypper addrepo https://download.opensuse.org/repositories/home:portalofreedom/15.6/home:portalofreedom.repo
zypper refresh
zypper install protobuf-c