Adding NXP NCI Hal implementation

 This is a combination of 4 commits.
 The first commit's message is:

This patch includes Hal implementation
of NXP's NCI based NFC controller.

 This is the 2nd commit message:

NCI support for NXP chipsets

Modified to run against a standard NCI stack, tested on bacon

Change-Id: I70d220524e07cc37e92524d0c043c7826cc02e4a

 This is the 3rd commit message:

pn547: Don't attempt to downgrade firmware

As we just found, this makes things go boom in bad ways

Change-Id: I381fcf77bea920b43f202e407ff0dd9626552bf9

 This is the 4th commit message:

pn54x: Rename path to prepare for merge w/ AOSP

NXP submitted a variant of pn547 to AOSP's gerrit, lets try
to rebase on it

Change-Id: I4c828fc691b1e63d794096561bd13f53fed6b829