[qemu]: Remove qemu_pipe.h and qemud.h headers.
These headers do not correspond to loadable HAL modules or corresponding
support code so must be removed from here.
<hardware/qemu_pipe.h> is removed and replaced by a new header
named <system/qemu_pipe.h> that provides a slightly different
API.
<hardware/qemud.h> is a header providing a wrapper around qemu pipes
for old emulator-specific code that relied on the obsolete 'qemud'
daemon. It can be removed by changing all clients to use
<system/qemu_pipe.h> instead.
BUG=25875346
Change-Id: I72242bbe8598164e0c9fee17dfa91ea97f9ad914
2 files changed
