The existing implementation of qmp_send() requires the caller to provide
a buffer which is of word-aligned. The underlying reason for this is
that message ram only supports word accesses, but pushing this
requirement onto the clients results in the same boiler plate code
sprinkled in every call site.

By using a temporary buffer in qmp_send() we can hide the underlying
hardware limitations from the clients and allow them to pass their
NUL-terminates C string directly.
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230811205839.727373-2-quic_bjorande@quicinc.comSigned-off-by: Bjorn Andersson <andersson@kernel.org>