soc: qcom: glink: add NULL check for edge_ctx

In function edge_name_to_ctx_create, NULL check is missing after
kzalloc for edge_ctx variable.

NULL check validation is added.

CRs-Fixed: 1086686
Change-Id: Icbffbd9d02df97bda531353c41a7025b95a53991
Signed-off-by: Dhoat Harpal <hdhoat@codeaurora.org>