staging/slicoss: Fix buffer possible overflow in slic_card_locate

smatch complains about a possible buffer overflow
slicoss.c:3651 slic_card_locate() error: buffer overflow
'physcard->adapter' 4 <= 4

If the for loop is not exited prematurely i++ is executed after the last
iteration and thus i can be 4, which is out of bounds for
physcard->adapter.

-> Add check for this condition and simplify the if statement by
inverting the condition.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>