perf build: Add libbabeltrace to build-test

'make build-test' doesn't test LIBBABELTRACE=1. It misses a building
failure caused by commit 41840d211c51 ("perf config: Move config
declarations from util/cache.h to util/config.h"), breaks bisect.

Add LIBBABELTRACE=1 to build-test.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1466818918-131281-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/make

@@ -81,6 +81,7 @@ make_no_libbionic   := NO_LIBBIONIC=1
 make_no_auxtrace    := NO_AUXTRACE=1
 make_no_libbpf	    := NO_LIBBPF=1
 make_no_libcrypto   := NO_LIBCRYPTO=1
+make_with_babeltrace:= LIBBABELTRACE=1
 make_tags           := tags
 make_cscope         := cscope
 make_help           := help
@@ -136,6 +137,7 @@ run += make_no_libaudit
 run += make_no_libbionic
 run += make_no_auxtrace
 run += make_no_libbpf
+run += make_with_babeltrace
 run += make_help
 run += make_doc
 run += make_perf_o