bluez4: added dependency on 'libsndfile1'

bluez4: added dependency on 'libsndfile1'

bluez4 detects and uses libsndfile1 and the compilation can fail with

| sbc/sbctester.c:32:21: fatal error: sndfile.h: No such file or directory
| ...
| compilation terminated.
| make[1]: *** [sbc/sbctester.o] Error 1

in rebuilds (image with libsndfile1 was built, then some change ->
bluez4 do_configure runs with libsndfile1 -> libsndfile1 gets removed
-> bluez4 do_compile fails).

As there is no trivial way to disable its detection and to make it a
PACKAGECONFIG option, 'libsndfile1' was put into static DEPENDS.

(From OE-Core rev: b9571256f8996d1eb4b9a09b3b5b862a13f1b414)

Signed-off-by: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>