Remove qemu dependency.

Remove obsolete pieces from libardware_legacy that were related
to QEMU (i.e. running the system image under emulation) but are
no longer used.

Note that qemu tracing isn't implemented by the emulator anymore
(and has been for a long time).

BUG=25875346

Change-Id: I2593fe9f90241af9c5076fa248c30e0d8ab5d663
7 files changed