To clear things up right away: This means there is no official .iso or .cso file that will run natively in the PPSSPP emulator.
While you cannot play Resident Evil 6 via PPSSPP, you can play other titles from the series using different methods: 1. PlayStation 1 (PS1) Classics on PPSSPP Resident Evil 6 Ppsspp Zip File Download Android
Play Resident Evil 4 (Wii/PS2 version via Dolphin or AetherSX2), Resident Evil: Revelations (native Android port exists), or the PS1 RE games via PPSSPP (PSX2PSP converted eboots). To clear things up right away: This means