new I4B driver v.1.5.2

[hselasky at c2i.net (Hans Petter Selasky)]

NOTE for FreeBSD-5-current: you might have to add flag MTX_RECURSE to mtx_init 
in the function  "snd_mtxcreate" in the file 
"/usr/src/sys/dev/sound/pcm/sound.c" else the kernel will panic when isdnphone 
connects. 

Yours
-HPS