video: atmel_lcdfb: Use common error handling code in atmel_lcdfb_of_init()

[SF Markus Elfring]

>> If you want to lower the size of strings in this driver, you can do it,
>> but not like this.
> 
> Just so we're clear, GCC already detects and combines it when you use
> the same string constant twice.

Do you distinguish between merging of constants and the combination
of statements for such an use case?

Regards,
Markus