rpm REFACTOR update libyang.spec from Fedora

libyang maintainer desired continuing with libyang package as opposed to
libyang2 - sync libyang.spec from Fedora upstream.
diff --git a/distro/pkg/rpm/libyang.spec b/distro/pkg/rpm/libyang.spec
new file mode 100644
index 0000000..217bdec
--- /dev/null
+++ b/distro/pkg/rpm/libyang.spec
@@ -0,0 +1,75 @@
+Name: libyang
+Version: {{ version }}
+Release: {{ release }}%{?dist}
+Summary: YANG data modeling language library
+Url: https://github.com/CESNET/libyang
+Source: libyang-%{version}.tar.gz
+License: BSD
+
+BuildRequires:  cmake
+BuildRequires:  gcc
+BuildRequires:  make
+BuildRequires:  pkgconfig(libpcre2-8) >= 10.21
+
+%package devel
+Summary:    Development files for libyang
+Requires:   %{name}%{?_isa} = %{version}-%{release}
+Requires:   pcre2-devel
+
+%package tools
+Summary:        YANG validator tools
+Requires:       %{name}%{?_isa} = %{version}-%{release}
+# This was not properly split out before
+Conflicts:      %{name} < 1.0.225-3
+
+%description devel
+Headers of libyang library.
+
+%description tools
+YANG validator tools.
+
+%description
+Libyang is YANG data modeling language parser and toolkit
+written (and providing API) in C.
+
+%prep
+%autosetup -p1
+mkdir build
+
+%build
+cd build
+cmake \
+    -DCMAKE_INSTALL_PREFIX:PATH=%{_prefix} \
+    -DCMAKE_BUILD_TYPE:String="Package" \
+    -DCMAKE_C_FLAGS="${RPM_OPT_FLAGS}" \
+    -DCMAKE_CXX_FLAGS="${RPM_OPT_FLAGS}" \
+    ..
+make
+
+%check
+cd build
+ctest --output-on-failure
+
+%install
+cd build
+make DESTDIR=%{buildroot} install
+
+%files
+%license LICENSE
+%{_libdir}/libyang.so.2
+%{_libdir}/libyang.so.2.*
+
+%files tools
+%{_bindir}/yanglint
+%{_bindir}/yangre
+%{_datadir}/man/man1/yanglint.1.gz
+
+%files devel
+%{_libdir}/libyang.so
+%{_libdir}/pkgconfig/libyang.pc
+%{_includedir}/libyang/*.h
+%dir %{_includedir}/libyang/
+
+%changelog
+* Fri Aug 06 2021 Jakub Ružička <jakub.ruzicka@nic.cz> - {{ version }}-{{ release }}
+- upstream package