/usr/share/ardour5/midi_maps/ is in ardour-data 1:5.12.0-3.
This file is owned by root:root, with mode 0o755.
..
/usr/share/ardour5/midi_maps/AKAI_MIDIMix_EQ_Mode.map
/usr/share/ardour5/midi_maps/AKAI_MIDIMix_Normal_Mode.map
/usr/share/ardour5/midi_maps/AKAI_MPK61.map
/usr/share/ardour5/midi_maps/AKAI_MPKmini.map
/usr/share/ardour5/midi_maps/Alesis_QX25.map
/usr/share/ardour5/midi_maps/Arturia_KeyLab49.map
/usr/share/ardour5/midi_maps/DDX3216.map
/usr/share/ardour5/midi_maps/Korg_nanoKONTROL.map
/usr/share/ardour5/midi_maps/Korg_nanoKONTROL2.map
/usr/share/ardour5/midi_maps/Korg_nanoKONTROL2_With_Master.map
/usr/share/ardour5/midi_maps/Korg_nanoKONTROL_Master.map
/usr/share/ardour5/midi_maps/Korg_nanoKONTROL_Studio.map
/usr/share/ardour5/midi_maps/Korg_taktile.map
/usr/share/ardour5/midi_maps/M-Audio_Axiom25.map
/usr/share/ardour5/midi_maps/M-Audio_Axiom61.map
/usr/share/ardour5/midi_maps/M-Audio_Axiom_Air_25_2015_Model_Transport_Only.map
/usr/share/ardour5/midi_maps/M-Audio_Oxygen49.map
/usr/share/ardour5/midi_maps/M-Audio_Oxygen61v3.map
/usr/share/ardour5/midi_maps/Novation Impulse 49.map
/usr/share/ardour5/midi_maps/Novation_Impulse61.map
/usr/share/ardour5/midi_maps/Novation_LaunchControl_XL.map
/usr/share/ardour5/midi_maps/Novation_LaunchKey25.map
/usr/share/ardour5/midi_maps/Roland_SI-24.map
/usr/share/ardour5/midi_maps/Roland_V_Studio_20.map
/usr/share/ardour5/midi_maps/Yamaha_KX25.map
/usr/share/ardour5/midi_maps/akai-mpd-32.map
/usr/share/ardour5/midi_maps/bcf2000.map
/usr/share/ardour5/midi_maps/bcf2000_mackie.map
/usr/share/ardour5/midi_maps/m-audio-oxygen61v3.map
/usr/share/ardour5/midi_maps/m-audio_oxygen25.map
/usr/share/ardour5/midi_maps/m-audio_oxygen8v2.map
/usr/share/ardour5/midi_maps/midikb_wiimote.map
/usr/share/ardour5/midi_maps/xboard-61.map