This patch adds support for partial reads to the CUSE swtpm.
We introduce a ptm_read_offset variable that holds the offset where to read
from next. It is reset every time a command has been processed as part of a
write() so that subsequent read()s start reading from offset 0. It is
advanced by the number of bytes that were read.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
