soc: qcom: smem_log: Use correct printk format specifier for size_t

%zu is the correct printk format specifier when printing size_t types.

Update printks to use %zu for size_t type variables.

Change-Id: I30284039ff9f468741741651bbb56924b56b1193
Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>