Closes Bears-R-Us#3679: Flatten and unflatten runtime checks failure (B…

…ears-R-Us#3680)

when building with with gasnet, runtime checks, and multi-dim, I was seeing some test failures with the following error:

```
arkouda//src/AryUtil.chpl:966: error: references to remote data cannot be passed to external routines like 'c_pointer_return'
```

This was caused by some `c_ptrTo` called on some remote values. This was definitely what was intended because we were passing the addresses to `get/put`. I looked into how this was handled in the aggregation code and found `getAddr` in `CommPrimitives`. I think this does the same thing as `c_ptrTo` but avoids the runtime check? I'm not sure but making the substitution seems to have fixed the issue

Co-authored-by: Tess Hayes <stress-tess@users.noreply.github.com>

src/AryUtil.chpl

@@ -14,6 +14,8 @@ module AryUtil
  use OS.POSIX;
  use List;
  use CommAggregation;
+ use CommPrimitives;
+
 
  param bitsPerDigit = RSLSD_bitsPerDigit;
  private param numBuckets = 1 << bitsPerDigit; // these need to be const for comms/performance reasons
@@ -902,7 +904,7 @@ module AryUtil
  // flat region sits within a single locale, do a single get
  get(
  c_ptrTo(unflat[low]),
- c_ptrToConst(a[flatSlice.low]):c_ptr(t),
+ getAddr(a[flatSlice.low]),
  locInStart,
  c_sizeof(t) * flatSlice.size
  );
@@ -913,7 +915,7 @@ module AryUtil
 
  get(
  c_ptrTo(unflat[dufc.orderToIndex(flatSubSlice.low)]),
- c_ptrToConst(a[flatSubSlice.low]):c_ptr(t),
+ getAddr(a[flatSubSlice.low]),
  locInID,
  c_sizeof(t) * flatSubSlice.size
  );
@@ -963,7 +965,7 @@ module AryUtil
  if locOutStart == locOutStop {
  // flat region sits within a single locale, do a single put
  put(
- c_ptrTo(flat[flatSlice.low]),
+ getAddr(flat[flatSlice.low]),
  c_ptrToConst(a[low]):c_ptr(t),
  locOutStart,
  c_sizeof(t) * flatSlice.size
@@ -974,7 +976,7 @@ module AryUtil
  const flatSubSlice = flatSlice[flatLocRanges[locOutID]];
 
  put(
- c_ptrTo(flat[flatSubSlice.low]),
+ getAddr(flat[flatSubSlice.low]),
  c_ptrToConst(a[dc.orderToIndex(flatSubSlice.low)]):c_ptr(t),
  locOutID,
  c_sizeof(t) * flatSubSlice.size