soc: qcom: smem: Renaming smem item SMEM_SMEM_STATIC_LOG_IDX

SMEM_SMEM_STATIC_LOG_IDX is currently unused as its usecase has
been deprecated for a long time. Reallocate the ID to
SMEM_XBL_LOADER_CORE_INFO.

CRs-Fixed: 998028
Change-Id: I5f80603633464e7eea322fde57110e377b72d84c
Signed-off-by: Dhoat Harpal <hdhoat@codeaurora.org>