[Bug] PrimeKB/Meridian LED indicator lights won't turn off.

Meridian's LED indicator lights won't turn off. Further more, it seems like rgblight_setrgb_at can no longer control the LEDs, which was previously working in the initial commit.

Describe the Bug

It seems like rgblight_setrgb_at no longer works properly for the Meridian firmwares (both VIA & default) on master. I'm not sure what could have caused it or if other STM32 related PCBs have the same issue. After git-bitsecting, I have narrowed it down to this commit to be the source of the problem.

System Information

• Keyboard:
  • Revision (if applicable): PrimeKB/Meridian (revision master)
• Operating system: macOS Mojave (v10.14.6)
• AVR GCC version: avr-gcc (Homebrew AVR GCC 8.4.0) 8.4.0
• ARM GCC version: arm-none-eabi-gcc (GNU Tools for Arm Embedded Processors 8-2019-q3-update) 8.3.1 20190703 (release) [gcc-8-branch revision 273027]
• QMK Firmware version: 0.11.56
• Any keyboard related software installed?
  • AutoHotKey
  • [x ] Karabiner
  • Other:

Additional Context

• git-bitsect points to this commit to be the source of the problem: https://github.com/qmk/qmk_firmware/commit/c66df1664497546f32662409778731143e45a552.