drivers: net: k61 : fail k61 probe if CAN MCU is not present

There may be cases when the K61 CAN MCU may not be connected.
Hence, fail the probe of K61 driver if we don't get a response
from the MCU so that the resources obtained can be deallocated.

Change-Id: I011661f8a97f803854679f347d8aea412558883d
Signed-off-by: Abinaya P <abinayap@codeaurora.org>