qseecom: fix secure app loading failure by kernel mode qseecom client

Fix secure app loading failure due to premature kzfree() from
__qseecom_load_fw(), when kernel mode qseecom client tries to
load app.

CRs-fixed: 694541
Change-Id: Ida43a6a8367aef0d0aa29ad5ad3eee802c816e87
Signed-off-by: William Clark <wclark@codeaurora.org>