OpenWRT Build System for CentOS 7

How does one create a "build system" (AKA Cross Compile / Cross-Compile / CrossCompile Build System) for OpenWRT? There are lots of tutorials;

• General Guide for building firmware: https://openwrt.org/docs/guide-user/additional-software/beginners-build-guide
  • Start of detailed Information: https://openwrt.org/docs/guide-developer/build-system/start
  • Pre-requisites for a : https://openwrt.org/docs/guide-developer/build-system/install-buildsystem
  • Some additional granular detail for working with specific versions: https://openwrt.org/docs/guide-developer/build-system/use-buildsystem
• Build environment tips: https://openwrt.org/docs/guide-developer/env
• SDK (for compiling specific packages): https://openwrt.org/docs/guide-developer/using_the_sdk
  • URL for SDK (look towards the bottom of the page for SDK): https://downloads.openwrt.org/releases/19.07.3/targets/mvebu/cortexa9/
• Third Party Site with nice information (Old, but this article itself notes even older OpenWRT documentation): http://www.acme-dot.com/building-openwrt-14-07-barrier-breaker-on-ubuntu-and-os-x/ (Don't follow the instructions as it GIT won't work anymore with non-SSL URLs)
• Entware Tips (The don't apply directly, but have some good tips if read from the context of OpenWRT)
  • Native Compilation: https://github.com/Entware/Entware-ng/wiki/Using-gcc-%28native-compilation%29
  • Compiling Packages from Source: https://github.com/Entware/Entware-ng/wiki/Compile-packages-from-sources
  • Creating Perl modules: https://github.com/Entware/Entware-ng/wiki/Self-installation-of-perl-modules

This is my version.

Details of objectives, etc.

• OpenWRT 19.07.03 (Linux Kernel 4.14.180)
• Linksys WRT3200ACM Platform Information (see here for additional information)
  • Marvell Armada 385 88F6820 SoS (System on a Chip)
  • Manufacturer: Marvell, MVEBU (Marvell Embedded Business Unit)
  • CPU Information
    • ARM Family: Cortex-A (32-bit)
    • ARM Architecture: ARMv7-A
    • ARM Core: Cortex-A9
    • OpenWRT Target and Package Details
      • MVEBU (Marvell Embedded Business Unit)
        • Targets Available: cortexa53, cortexa72, cortexa9
    • Equivalent DD-WRT / Entware Target and Package reference
      • ARMv7sf-k3.2: ARM version 7 with linux kernel 3.2
  • Sources:
    • https://en.wikipedia.org/wiki/List_of_ARM_microarchitectures
    • https://en.wikipedia.org/wiki/ARM_Cortex-A9
    • http://bin.entware.net/mipselsf-k3.4/

There seem to be some missing packages in CentOS 8, so CentOS 7.8 was chosen for this project.