Remove libbpf

Remove libbpf as discussed in #948041 RFS for new package opened at #950760

debian/rules.d/tools/lib/bpf/Makefile

-include $(top_rulesdir)/Makefile.inc
-
-DEB_HOST_MULTIARCH := $(shell dpkg-architecture -qDEB_HOST_MULTIARCH)
-
-# Catch use of missing kernel APIs early
-CFLAGS += -Werror=implicit-function-declaration
-
-# Don't let the kernel version override libbpf's version
-undefine VERSION
-
-MAKE_BPF := +$(MAKE) -C $(top_srcdir)/$(OUTDIR) O=$(CURDIR)
-MAKE_BPF += prefix=/usr
-MAKE_BPF += libdir_relative=lib/$(DEB_HOST_MULTIARCH)
-MAKE_BPF += V=$(KBUILD_VERBOSE)
-MAKE_BPF += ARCH=$(KERNEL_ARCH)
-
-all:
-	$(MAKE_BPF)
-
-install:
-	$(MAKE_BPF) install install_headers