[bluez] update hciattach to BlueZ 5 version

BlueZ 5 hciattach has some improvements, such as support for Broadcom
43xx chips. Copied the sources from BlueZ 5.22 with minor
modifications:

- added the possibility to specify firmware binary directory in
  command line arguments

- changed locating the firmware binary file to use case-insensitive
  matching.

- added the possibility to read the BT address from a file instead
  of being directly specified on the command line
Merge pull request #43 from hmallat/bluez5-hciattach

[bluez] update hciattach to BlueZ 5 version