[keymgr_dpe/dv] Improve pass rate of `keymgr_dpe_smoke`

@bobby-rivos is already working on this.

Since Jan 29, 2024.

The `keymgr_dpe_smoke` test currently has a pass rate of about 97%. For a smoke test, we would expect a pass rate >99%, but `keymgr_dpe_smoke` has significantly more coverage than the usual smoke test and thus is also a lot more complex. Still, we should improve its pass rate substantially.

Before PR #20485, the pass rate of that test was >99%.

Before PR #21135, the pass rate was about 68%.

The main failure buckets are the following:

```
* `UVM_ERROR (keymgr_dpe_scoreboard.sv:567) scoreboard [scoreboard] After a disable kmac sideload key was not presevedexp * vs. act *` has 10 failures:
* Test keymgr_dpe_smoke has 10 failures.
* 26.keymgr_dpe_smoke.2134254108\
Line 3095, in log /home/dev/src/scratch/keymgr_dpe_smoke_pass_rate/keymgr_dpe-sim-xcelium/26.keymgr_dpe_smoke/latest/run.log

UVM_ERROR @ 6779585532 ps: (keymgr_dpe_scoreboard.sv:567) uvm_test_top.env.scoreboard [uvm_test_top.env.scoreboard] After a disable kmac sideload key was not presevedexp 'h947737d90049f004f9f8ef7136c2d665983d5d92118d6c06fc91c7ff3942154b20c70de75a49436a9de8b5abd32056d23848de2793ed6c735119589d7a730df1 vs. act 'h0
UVM_INFO @ 6779585532 ps: (uvm_report_catcher.svh:705) [UVM/REPORT/CATCHER]
--- UVM Report catcher Summary ---

* 163.keymgr_dpe_smoke.2424040788\
Line 2790, in log /home/dev/src/scratch/keymgr_dpe_smoke_pass_rate/keymgr_dpe-sim-xcelium/163.keymgr_dpe_smoke/latest/run.log

UVM_ERROR @ 18638430602 ps: (keymgr_dpe_scoreboard.sv:567) uvm_test_top.env.scoreboard [uvm_test_top.env.scoreboard] After a disable kmac sideload key was not presevedexp 'h1456aea969399e870cdf83b2ccc047fd79d5268b7d40e264d25e55bdab617bdf21fad43bf3730e8e5e82634171d68874eb38f560bf1ab00f321a1afd7955109f vs. act 'h0
UVM_INFO @ 18638430602 ps: (uvm_report_catcher.svh:705) [UVM/REPORT/CATCHER]
--- UVM Report catcher Summary ---

* ... and 8 more failures.
```
```
* `UVM_FATAL (uvm_phase.svh:1521) [PH_TIMEOUT] Explicit timeout of * ps hit, indicating a probable testbench issue` has 1 failures:
* Test keymgr_dpe_smoke has 1 failures.
* 17.keymgr_dpe_smoke.655049203\
Line 2699, in log /home/dev/src/scratch/keymgr_dpe_smoke_pass_rate/keymgr_dpe-sim-xcelium/17.keymgr_dpe_smoke/latest/run.log

UVM_FATAL @ 200000000000 ps: (uvm_phase.svh:1521) [PH_TIMEOUT] Explicit timeout of 200000000000 ps hit, indicating a probable testbench issue
UVM_INFO @ 200000000000 ps: (uvm_report_catcher.svh:705) [UVM/REPORT/CATCHER]
--- UVM Report catcher Summary ---
```
```
* `UVM_ERROR (cip_base_scoreboard.sv:282) scoreboard [scoreboard] alert recov_operation_err did not trigger max_delay:*` has 1 failures:
* Test keymgr_dpe_smoke has 1 failures.
* 295.keymgr_dpe_smoke.2035463257\
Line 2539, in log /home/dev/src/scratch/keymgr_dpe_smoke_pass_rate/keymgr_dpe-sim-xcelium/295.keymgr_dpe_smoke/latest/run.log

UVM_ERROR @ 4687220038 ps: (cip_base_scoreboard.sv:282) uvm_test_top.env.scoreboard [uvm_test_top.env.scoreboard] alert recov_operation_err did not trigger max_delay:0
UVM_INFO @ 4687220038 ps: (uvm_report_catcher.svh:705) [UVM/REPORT/CATCHER]
--- UVM Report catcher Summary ---
```