bluetooth: Use bt_vendor.conf to set correct..

..firmware patch file name

Z2: Chipset BCM4335C0
Z3: Chipset BCM4350C0

* libbt(-vendor) expects the filename to match
  the chipset reported, but we have a different
  common filename (from Sony stock).
* Add bt_vendor.conf to set the correct name
  instead of creating symlinks to what was expected.

Change-Id: I78fa158d052b1913284c55d7f01eef9508b975fe