Set as-instr to use printf intsead of echo

as-instr was hardcoded to use /bin/echo with the -e option.
Non-GNU systems like MacOSX would fail and cause compiler errors.

Since BSD echo does not have the -e option (escape backslashes)
prinf was used instead would should be more friendly cross-platform

Specifically with the new OSX toolchain it caused the following
error:
  Error: selected processor does not support ARM mode `smc #0'

This was caused by $(call as-instr,.arch_extension sec,+sec) failing
since it was using echo -e.

See: http://pubs.opengroup.org/onlinepubs/9699919799/utilities/echo.html

  "It is not possible to use echo portably across all POSIX systems
   unless both -n (as the first argument) and escape sequences are
   omitted.

  The printf utility can be used portably to emulate any of the
  traditional behaviors of the echo utility as follows (assuming
  that IFS has its standard value or is unset)

  New applications are encouraged to use printf instead of echo."

Change-Id: I558ec343e9bb8d449e1af710d329b4dc76743a05
steelhead: Configure BT_HOST_WAKE gpio as input pulldown

Copy over commit 28a1255b5753a7c413e650bd533e3dc9d5d5a276

    OMAP4 tuna: Configure BT_HOST_WAKE gpio as input pulldown

    The host_wake of bcm4330 need to be pulled low, not left floating.