Fill in missing requirements rationale

[skliper]

Checklist (Please check before submitting)

• I reviewed the Contributing Guide.
• I reviewed the README file to see if the feature is in the major future work.
• I performed a cursory search to see if the feature request is relevant, not redundant, nor in conflict with other tickets.

Is your feature request related to a problem? Please describe.
MM3400 and MM3500 requirements rationale are empty:

MM/docs/mm_FunctionalRequirements.csv

Lines 73 to 74 in 71d2ff4

	MM3400,MM3400,"Upon receipt of an Enable EEPROM command, MM shall enable the command specified bank of EEPROM for writing.",
	MM3500,MM3500,"Upon receipt of a Disable EEPROM command, MM shall disable/lock the command specified bank of EEPROM from being written to.",

Describe the solution you'd like
Fill in

Describe alternatives you've considered
None

Additional context
None

Requester Info
Jacob Hageman - NASA/GSFC