soc: qcom: hab: Add sanity check for payload_count

When handling memory import, payload_count is used for memory alloc
calculation. If the payload_count is too large, size will overflow
when creating page list.
Adding a sanity check for payload_count is necessary.

Change-Id: I6d60cea0c62bd29092852c55b766b77a94cb6e3b
Signed-off-by: lixiang <lixiang@codeaurora.org>