projects/ad9467_fmc: Add txt pinout file for AD9467-FMC

[hadarauelena]

PR Description

Added AD9467-FMC pinout TXT file and FMC pin column in the Zed constraint file.
The AD9467-FMC schematic that was used can be found here.

PR Type

• Bug fix (change that fixes an issue)
• New feature (change that adds new functionality)
• Breaking change (has dependencies in other repos or will cause CI to fail)
• Documentation

PR Checklist

• I have followed the code style guidelines
• I have performed a self-review of changes
• I have compiled all hdl projects and libraries affected by this PR
• I have tested in hardware affected projects, at least on relevant boards
• I have commented my code, at least hard-to-understand parts
• I have signed off all commits from this PR
• I have updated the documentation (wiki pages, ReadMe files, Copyright etc)
• I have not introduced new Warnings/Critical Warnings on compilation
• I have added new hdl testbenches or updated existing ones

[cristianmihaipopa]

I double-checked the pins too and it seems fine to me. Also build the project and didn't catch anything.