fsi: sbefifo: Implement FSI_SBEFIFO_READ_TIMEOUT_SECONDS ioctl

FSI_SBEFIFO_READ_TIMEOUT_SECONDS ioctl sets the read timeout (in
seconds) for the response received by sbefifo device from sbe.  The
timeout affects only the read operation on current sbefifo device fd.

Certain SBE operations can take long time to complete and the default
timeout of 10 seconds might not be sufficient to start receiving
response from SBE.  In such cases, allow the timeout to be set to the
maximum of 120 seconds.

The kernel does not contain the definition of the various SBE
operations, so we must expose an interface to userspace to set the
timeout for the given operation.

Signed-off-by: Amitay Isaacs <amitay@ozlabs.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20220121053816.82253-3-joel@jms.id.au


Signed-off-by: Joel Stanley <joel@jms.id.au>