soc: qcom: smem: always ignore partitions with 0 offset or size

In qcom_smem_enumerate_partitions(), any partition table entry
having a zero offset or size field is ignored.  Move those checks
earlier in the loop, because there's no sense in examining the
host fields for those entries.

Add the same checks in qcom_smem_set_global_partition(), so the
scan for the global partition skips over these invalid entries.
This allows a later check for zero size or offset once the global
entry is found to be eliminated.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>