libbabeltrace feature detection message

[Arnaldo Carvalho de Melo]

Hi Jiri,

	While testing a patch by Wang, that requires building with
libbabeltrace, I noticed that there are no feature detection message
telling that it was found successfully. The end result is the desired
one, it builds with babeltrace, but I wonder if we couldn't have the
[ok] line for it:


[acme@jouet linux]$ rm -rf /tmp/build/perf ; mkdir -p /tmp/build/perf ; make LIBBABELTRACE=1 O=/tmp/build/perf -C tools/perf install-bin
make: Entering directory '/home/acme/git/linux/tools/perf'
  BUILD:   Doing 'make -j4' parallel build

Auto-detecting system features:
...                         dwarf: [ on  ]
...                         glibc: [ on  ]
...                          gtk2: [ on  ]
...                      libaudit: [ on  ]
...                        libbfd: [ on  ]
...                        libelf: [ on  ]
...                       libnuma: [ on  ]
...        numa_num_possible_cpus: [ on  ]
...                       libperl: [ on  ]
...                     libpython: [ on  ]
...                      libslang: [ on  ]
...                     libcrypto: [ on  ]
...                     libunwind: [ on  ]
...            libdw-dwarf-unwind: [ on  ]
...                          zlib: [ on  ]
...                          lzma: [ on  ]
...                     get_cpuid: [ on  ]
...                           bpf: [ on  ]

  GEN      /tmp/build/perf/common-cmds.h
  CC       /tmp/build/perf/fixdep.o
  LD       /tmp/build/perf/fixdep-in.o
<SNIP>
[acme@jouet linux]$ ldd ~/bin/perf | grep babel
	libbabeltrace-ctf.so.1 => /lib64/libbabeltrace-ctf.so.1 (0x00007fce5c405000)
	libbabeltrace.so.1 => /lib64/libbabeltrace.so.1 (0x00007fce5bd69000)
[acme@jouet linux]$ 


- Arnaldo