lib: Fix compilation error with musl
lib: Fix compilation error with musl

  CC       lib/hci.lo
In file included from lib/hci.c:39:0:
/usr/include/sys/poll.h:1:2: error: #warning redirecting incorrect
   #include <sys/poll.h> to <poll.h> [-Werror=cpp]
 #warning redirecting incorrect #include <sys/poll.h> to <poll.h>
  ^
cc1: all warnings being treated as errors

mapfau/bluez,ComputeCycles/bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,ComputeCycles/bluez,pstglia/external-bluetooth-bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,pkarasev3/bluez,silent-snowman/bluez,mapfau/bluez,pkarasev3/bluez,silent-snowman/bluez,ComputeCycles/bluez,pstglia/external-bluetooth-bluez,ComputeCycles/bluez,pkarasev3/bluez,mapfau/bluez,mapfau/bluez,pkarasev3/bluez