ci(measured_boot): update expect script to check non-zero PCR1 value

Updated expect script to check the non-zero value of PCR1 as it contains
the measurement of critical data.

Change-Id: I03c52fddb9e7caf7e8009d7b7524ba5a20c2e1ca
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
3 files changed