soc: qcom: minidump: check the size parameter passed to qcom_smem_get()

The size parameter passed to qcom_smem_get() can become less than
global toc size, add check to avoid out of bound accessing.

Change-Id: I068b4d5e27e94ce23c26856dad106a3970fb56d6
Signed-off-by: Srinivasarao Pathipati <quic_c_spathi@quicinc.com>