Use -j1

Signed-off-by: David Abdurachmanov <david.abdurachmanov@gmail.com>

libftdi.spec

@@ -1,6 +1,6 @@
 Name:		libftdi
 Version:	1.3
-Release:	11%{?dist}
+Release:	11.0.riscv64%{?dist}
 Summary:	Library to program and control the FTDI USB controller
 
 Group:		System Environment/Libraries
@@ -88,13 +88,13 @@ export CMAKE_PREFIX_PATH=/usr
 mkdir build-py2
 pushd build-py2
 %{cmake} -DPython_ADDITIONAL_VERSIONS=%{python2_version} ..
-make %{?_smp_mflags}
+make -j1
 popd
 
 mkdir build-py3
 pushd build-py3
 %{cmake} -DPython_ADDITIONAL_VERSIONS=%{python3_version} ..
-make %{?_smp_mflags}
+make -j1
 popd
 
 # Fix python sheband lines
@@ -180,6 +180,9 @@ rm -rf $RPM_BUILD_ROOT/%{_datadir}/doc/libftdi1/example.conf
 %postun c++ -p /sbin/ldconfig
 
 %changelog
+* Tue Jun 26 2018 David Abdurachmanov <david.abdurachmanov@gmail.com> - 1.3-11.0.riscv64
+- Use -j1 to avoid issue with Error: Unable to find 'ftdi1_doc.i'
+
 * Wed Feb 07 2018 Fedora Release Engineering <releng@fedoraproject.org> - 1.3-11
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_28_Mass_Rebuild