Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1454089805-5470-11-git-send-email-peter.maydell@linaro.org

The macro g_assert_not_reached is a better self documenting replacement
for assert(0) or assert(false).
Signed-off-by: NStefan Weil <sw@weilnetz.de>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

Signed-off-by: NDmitry Fleytman <dmitry@daynix.com>
Signed-off-by: NYan Vugenfirer <yan@daynix.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>