This repo should be used as following steps:
# Download kernel-alt-4.14.0-115.el7a.0.1.src.rpm
$ wget https://archive.kernel.org/centos-vault/altarch/7.6.1810/os/Source/SPackages/kernel-alt-4.14.0-115.el7a.0.1.src.rpm
$ rpm -ivh kernel-alt-4.14.0-115.el7a.0.1.src.rpm

# Add these patches to SOURCES directory
$ cp -f *patch ~/rpmbuild/SOURCES/
$ cp -f kernel-alt-4.14.0-aarch64.config ~/rpmbuild/SOURCES/
$ cp -f kernel-alt-4.14.0-aarch64-debug.config ~/rpmbuild/SOURCES/

# Replace spec by using spec here
$ cp -f kernel-alt.spec ~/rpmbuild/SPECS/

# Start rpmbuilding
$ cd ~/rpmbuild/SPECS/
$ rpmbuild -bb kernel-alt.spec
$ cd ~/rpmbuild/RPMS/aarch64
$ rpm -ivh kernel-4.14.0-115.el7.0.2.aarch64.rpm