DAOS-16979 control: Reduce frequency of hugepage allocation at runtime

[tanabarr]

Test-tag-hw-medium: pr daily_regression
Allow-unstable-test: true

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[github-actions]

Ticket title is 'Mitigation against hugepage memory fragmentation'
Status is 'To Do'
https://daosio.atlassian.net/browse/DAOS-16979

[tanabarr]

@phender as discussed in order to try to reproduce the DMA grow failure (DAOS-16979) related to hugepage fragmentation I ran this PR with Test-tag-hw-medium: pr daily_regression to try to trigger the failure. Unfortunately https://build.hpdd.intel.com/blue/organizations/jenkins/daos-stack%2Fdaos/detail/PR-15848/1/pipeline/ didn't hit the issue. any other ideas on how to get a baseline to prove a fix? or any other approaches like just landing a fix and seeing if it has the desired result? I'm going to try to generate a local reproducer as well.