DAOS-16953 tests: fix btree parameter parsing

[grom72]

Backoprt #15850

In btree.sh the -m and -t parameters were not applied correctly because of the preceding positional argument containing spaces but not wrapped in quotes

In btree.c an invalid parameter sequence was not detected due to of the partially manual parsing process.

All parameters parsing process has been unified.

Additionally:
instead of -t and -m parameters new parameters has been proposed:

-R[d] for class registration, optionally with dynamic root -M[p] for memory registration, optionally with indication to use persistent memory struct btr_test_state introduced to provide global parameters to the test (argc/argv) and avoid static variables for that purpose.

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[github-actions]

Ticket title is 'btree.sh argument parsing is off'
Status is 'In Review'
https://daosio.atlassian.net/browse/DAOS-16953

[jolivier23]

Looks fine but why do we need to backport a test?