PF_PACKET support is not enabled by setting ac_libnet_have_pf_packet but by setting libnet_cv_have_packet_socket
in the Makefile
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
The correct includes for musl are protected by an __GLIBC__ check in the
upstream sources.
Since musl does not provide own defines to identify itself, simply invert
the condition to !__UCLIBC__ in order to fix the build on all libc flavors
supported by OpenWrt.
Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>