Fix Makefile's diagnostic diff output when there is LIBBPF_API-versioned
symbols mismatch.
Fixes: 1bd63524593b ("libbpf: handle symbol versioning properly for libbpf.a")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191127200134.1360660-1-andriin@fb.com
                     "versioned symbols in $^ ($(VERSIONED_SYM_COUNT))." \
                     "Please make sure all LIBBPF_API symbols are"       \
                     "versioned in $(VERSION_SCRIPT)." >&2;              \
-               readelf -s --wide $(OUTPUT)libbpf-in.o |                 \
+               readelf -s --wide $(BPF_IN_SHARED) |                     \
                    cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' |   \
                    awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$8}'|   \
                    sort -u > $(OUTPUT)libbpf_global_syms.tmp;           \