Merge tag 'pull-hv-balloon-20240308' of https://github.com/maciejsszmigiero/qemu into staging

Hyper-V Dynamic Memory and VMBus misc small patches

This pull request contains two small patches to hv-balloon:
the first one replacing alloca() usage with g_malloc0() + g_autofree
and the second one adding additional declaration of a protocol message
struct with an optional field explicitly defined to avoid a Coverity
warning.

Also included is a VMBus patch to print a warning when it is enabled
without the recommended set of Hyper-V features (enlightenments) since
some Windows versions crash at boot in this case.

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* tag 'pull-hv-balloon-20240308' of https://github.com/maciejsszmigiero/qemu:
  vmbus: Print a warning when enabled without the recommended set of features
  hv-balloon: define dm_hot_add_with_region to avoid Coverity warning
  hv-balloon: avoid alloca() usage

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>