vendorcode/siemens: Ensure a given info block is available for a field

While searching for a field in all blocks ensure that the checked block
is available and can be used. In this way a field can be retrieved from
every block and not just the first one.

Change-Id: Idbd7656ab0664763cb065f5e817193ad1d9e0871
Signed-off-by: Werner Zeh <werner.zeh@siemens.com>
Reviewed-on: https://review.coreboot.org/17670
Tested-by: build bot (Jenkins)
Reviewed-by: Mario Scheithauer <mario.scheithauer@siemens.com>
1 file changed