[PATCH resent] drm/amd/display: Fix exception handling in dm_validate_stream_and_context()

[Markus Elfring]

>> The label “cleanup” was used to jump to another pointer check despite of
>> the detail in the implementation of the function “dm_validate_stream_and_context”
>> that it was determined already that corresponding variables contained
>> still null pointers.
>>
>> 1. Thus return directly if
>>    * a null pointer was passed for the function parameter “stream”
>>      or
>>    * a call of the function “dc_create_plane_state” failed.
>>
>> 2. Use a more appropriate label instead.
>>
>> 3. Delete two questionable checks.
>>
>> 4. Omit extra initialisations (for the variables “dc_state” and “dc_plane_state”)
>>    which became unnecessary with this refactoring.
>>
>>
>> This issue was detected by using the Coccinelle software.
>>
>> Fixes: 5468c36d628524effbb89a9503eb1a2318804759 ("drm/amd/display: Filter Invalid 420 Modes for HDMI TMDS")
>
> Please truncate the hash to 12 characters.

May longer identifiers (or even the complete SHA-1 ID) occasionally also
be tolerated for the tag “Fixes”?

How do you think about the proposed change possibilities?

Regards,
Markus