staging: slicoss: remove default case after we done with request_firmware

we are returning -ENOENT when there is no firmware file for a matching
device id. then we start calling request_firmware,
after this we do checks on the firmware length of corresponding
device id, since the default case is handled in the begining itself
there is no need of a default case at the firmware length checks

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>