If swtpm becomes unresponsive, guest gets blocked at "recvmsg" on tpm's
data FD. This change adds a timeout to the data fd socket. If swtpm
becomes unresponsive guest waits for "timeout" (secs) and continues to
run after returning an I/O error to tpm commands.
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>