[refactor/fix] use uuid in user-side request type

Since vector resize can cause pointers into the vector to become
invalid, this patch introduces a level of indirection for DMAs and
Scratchs, using uuid on the user-side of a request to index into the
request vector.
5 jobs for fix-async-requests in 26 minutes and 29 seconds
Status Job ID Name Coverage
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passed #44504
integration
checkpatch

00:00:09

passed #44503
integration
repoquality

00:01:44

 
  Build
passed #44505
make:generic

00:08:52

passed #44507
knl
make:knl

00:07:05

passed #44506
make:out-of-tree

00:08:48