qseecom: Support Non-contiguous ION allocated memory

Get the scatter gather entries for non contiguous Ion
allocated memory and populate the list within the command
message with the physical address of each chunks.

Change-Id: I0e8d930525f50b6aac38b0bd3e7debec9024d1f0
Signed-off-by: Mona Hossain <mhossain@codeaurora.org>