Installing IP-Route Extension for MP-TCP on LEDE

I am trying to install ip-route extension to be able to enable/disable multipath operation on a specific interface. However, when I check the output of ./configure and I getting some missing dependencies that are necessary for compiling ip-route extension. Here is the output of ./configure:

TC schedulers
ATM no
IPT Package xtables was not found in the pkg-config search path.
Perhaps you should add the directory containing `xtables.pc'
to the PKG_CONFIG_PATH environment variable
No package 'xtables' found
using iptables
IPSET no

iptables modules directory: Package xtables was not found in the pkg-config search path.
Perhaps you should add the directory containing `xtables.pc'
to the PKG_CONFIG_PATH environment variable
No package 'xtables' found
not found!
libc has setns: no
SELinux support: no
ELF support: no
libmnl support: no
Berkeley DB: no

docs: latex: no
WARNING: no docs can be built from LaTeX files
sgml2html: no
WARNING: no HTML docs can be built from SGML

My current problem is how to install xtables.pc, I already enabled netfilter in kernel_menuconfig but I am still getting the same error 'xtables.pc not found'

Without ip-route extension mptcp is enabled by default on all the interfaces. There is already an apt-get package for it but for LEDE I did not find anything. Any help is appreciated.