This optimization was only written for Ampere1A where it showed a
noticable performance improvement in #5321. On Cortex it didn't matter.
Turns out this actually hits a bad case on Oryon CPUs where `dc zva` is
actually dramatically slower in the face of memory barriers and
overlapping stores in flight.
So now just detect Ampere and only use the optimization on that hardware
and send everyone else down the regular path.
microbench A1A:
```
Cycle counter frequency: 1000000000
Cycle counter granularity: 20
ns in cycle: 1
suite: memory
Test, Total Cycles, Iterations, Cycles Average, Iter Time Average, iterations/Second
dc zva - vzeroupper, 723390880, 363855872, 1.99, 1.99 nanosecond, 502986534.75
dc zva - vzeroall, 571708060, 161742848, 3.53, 3.53 nanosecond, 282911610.52
dc zva (stp emu) - vzeroupper, 541543980, 107872256, 5.02, 5.02 nanosecond, 199193897.42
dc zva (stp emu) - vzeroall, 722548940, 71958528, 10.04, 10.04 nanosecond, 99589832.63
```
microbench X2E:
```
Cycle counter frequency: 19200000
Cycle counter granularity: 1
ns in cycle: 52.083333333333336
suite: memory
Test, Total Cycles, Iterations, Cycles Average, Iter Time Average, iterations/Second
dc zva - memset 0, 12065162, 49, 246227.80, 12.82 millisecond, 77.98
dc zva - vzeroupper, 12098598, 4325376, 2.80, 145.68 nanosecond, 6864201.89
dc zva - vzeroall, 12031459, 4325376, 2.78, 144.87 nanosecond, 6902506.11
dc zva (stp emu) - vzeroupper, 13899441, 363855872, 0.04, 1.99 nanosecond, 502612496.60
dc zva (stp emu) - vzeroall, 12389283, 161742848, 0.08, 3.99 nanosecond, 250657175.37
```
We are actually quite close to a single page of CPU state per thread and
any additional changes are likely to cause it to overflow which would
hit these asserts. As we saw with the libc++ implementation of mutexes,
just one object type changing size could push it over the edge.
Future proof this by ensuring we can have this be sixteen pages per
thread before needing to hit more complex implementations. Which I don't
see us getting that large of CPU context tracking.
Implicitly adding "-c" breaks argument passing for scripts. For example, the
command "FEXBash ./steam.sh -silent" will process steam.sh but the script
wouldn't see the "-silent" argument previously.
coredump applications aren't smart enough to only dump resident pages,
so explicitly mark our 128TB and other mapped VA ranges as DONTDUMP.
This will speed up coredumps.
To not have this environment variable accidently be enabled on arm64
native Wine games, we need to set it from inside of FEX.
Requires the FEX dlls to set them directly rather than launch scripts.
LC