[rpcrt4] Fix RpcMgmtSetServerStackSize prototype (2nd attempt)

[Vitaliy Margolen]

Vitaliy Margolen wrote:
> Thomas Weidenmueller wrote:
>> The parameter of RpcMgmtSetServerStackSize needs to be unsigned long,
>> not unsigned int.
>>
>> - Thomas
>>
> It's been discussed numerous times, you should avoid use of 'long' in
> Wine. On win64 sizeof(long) == 4. On Linux64 sizeof(long) == 8.
> 
I will answer myself: it is declared as 'unsigned long' in SDK.

Sorry for the noise.

Vitaliy