Crypto enhancement

[mojtaba-bisheh]

Enhanced crypto modules including:

1. remove deadcode in doe_core_cbc (found by FPV)
   dead code in line 254-255 doe_core_cbc.sv:
   else if(enc_ready)
   IV_enc_state <= st_IV_engine_idle;

2. froze adder inputs to fix [ECC] add_sub_mod_alter ready not aligned with result  #194 (found by FPV)
   With this PR, there is no more constraints on keeping inputs fixed. The only constraint is having a single pulse add_en_i, and do not enable it again until ready_o.

3. remove sca_en_i since countermeasures are hardcoded to be enabled (found by FPV)

4. remove deadcode in ecc_pm_ctrl:163 (found by FPV)
   in ecc_pm_ctrl:163 the last else if () is always taken. This PR switches to just else to avoid confusion.

5. Stop faulty ECC from continuing before zeroize (found by FPV): When the error happens for the first time, the error flag goes high and will remain high until zeroize. We expect that uC issues zeroize if there is an error in ECC. In this scenario, although the second command will be performed, the results should not be used since error flag is kept high. However, this PR stops faulty ECC from continuing before zeroize.

6. removed one cycle delay for hmac_drbg ready (found by FPV)
   This PR synchronizes hmac_drbg READY to VALID by removing one cycle delay

7. add all_1 protection for LFSR
   This PR has protection for the LFSR to stuck to be all 1.

8. Remove zeroize for the counter used as countermeasure (found by IOActive)

9. Remove one extra iteration in ecc_scalar_blinding (found by FPV)
   In line 300 of scalar_blinding, we have a loop of 20 iterations (0 to 19). However, when we enter the last round, the scalar blinding flag changes to done and we don't perform the last iteration. This PR reduces the iteration by one by updating FULL_DIG_NUM.

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