[PATCH] linux: Remove assembly umount2 implementation

[Adhemerval Zanella]

On 08/05/2020 11:48, Florian Weimer wrote:
> * Adhemerval Zanella via Libc-alpha:
> 
>> Only alpha and ia64 do not support __NR_umount2 (defined as
>> __NR_umount), but recent kernel fixes (74cd2184833f for ia64, and
>> 12b57c5c70f39 for alpha) add the required alias.
> 
> Shouldn't this be in a separate umount2.c file, based on the existing
> conventions?
> 

I don't have a strong opinion here. I added in the umount implementation
just to avoid add a hidden_def/hidden_proto and a new file.