[dv/hmac] fix_reset_corner_case
[dv/hmac] fix_reset_corner_case

Recently Hmac updated to delete tlul interface probing. Found a corner
case with reset: when reset signal is low, scoreboard's
`hmac_process_fifo_rw` did not gate the
rst signal, thus still increase the wr_cnt during reset. Here added a gating signal
for reset.
Scb flush function, add a statement to reset the `wr_cnt_updated` back
to 1. In case deadloop.

Signed-off-by: Cindy Chen <399ad771a111eac8923348b1e2af093034e5d4f1@google.com>

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