Proceed as usual (assuming you sourced the activate-script-helpers script appropriate for your toolchain)
$ source env.src
$ tar -xvzf libpcap-1.8.1.tar.gz
$ cd libpcap-1.8.1
$ ./configure --prefix=$ROOT --host=$TARGET_HOST CFLAGS="$CFLAGS"
$ make -j && make install
You should have a statically library for libpcap for that architecture, confirm with:
$ file libpcap.so
libpcap.so: current ar archive