pwm: atmel-tcb: Delete an error message for a failed memory allocation in atmel_tcb_pwm_probe()

[SF Markus Elfring]

>> Omit an extra message for a memory allocation failure in this function.
>>
>> This issue was detected by using the Coccinelle software.
> 
> Can you point which coccinelle script highlited this issue?

Not directly (so far).

I constructed an approach for the semantic patch language based on
information from the script “checkpatch.pl”.
Would you like to improve it any ways?

Regards,
Markus