RFR: 8231952: ARM32: Wrong assumption in assertion in LIRGenerator::atomic_xchg and LIRGenerator::atomic_add

[christoph.goettschkes at microdoc.com]

Hi Aleksey,

> Looks good to me.
> 
> You need a sponsor for this? Is Boris sponsoring?

thanks for your review. I am fairly new to the process of pushing changes 
into the OpenJDK. By sponsor you mean someone who can push the changeset 
into the repository? For my previous changes, Boris was so kind and did 
that for me. I would ask him again if he could so, but if its possible for 
you as well, I am fine with that too. Boris created the issues in the JBS 
for me though.

Thanks, Christoph