[MYRI_SBUS]: Prevent that myri_do_handshake lies about ticks.

With '<=' tick can be incremented up to 26, The last loop is redundant
since even when 'softstate' becomes 'STATE_READY', 'if (tick > 25)'
will still cause the function to return -1,

Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>