tpm2_tlcl: Use signed integer for tpm2_marshal_command return value
The tpm2_marshal_command() function returns a negative value on error,
so we must use a signed type for the return value.
This was found by the coverity scan:
https://scan.coverity.com/projects/coreboot?tab=overview
CID:
1357675
CID:
1357676
Change-Id: I56d2ce7d52b9b70e43378c13c66b55ac2948f218
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Found-by: Coverity Scan
Reviewed-on: https://review.coreboot.org/15717
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>