Makefile.include/term: define 'flash/flash-only' as TERMFLASHDEPS
Makefile.include/term: define 'flash/flash-only' as TERMFLASHDEPS

This puts the handling of `flash/flash-only` in common for both
`term/cleanterm` commands.

OlegHahm/RIOT,josephnoir/RIOT,jasonatran/RIOT,OlegHahm/RIOT,authmillenon/RIOT,aeneby/RIOT,kYc0o/RIOT,josephnoir/RIOT,ant9000/RIOT,yogo1212/RIOT,OTAkeys/RIOT,yogo1212/RIOT,OlegHahm/RIOT,ant9000/RIOT,RIOT-OS/RIOT,RIOT-OS/RIOT,toonst/RIOT,mtausig/RIOT,miri64/RIOT,josephnoir/RIOT,mtausig/RIOT,OlegHahm/RIOT,kaspar030/RIOT,jasonatran/RIOT,OTAkeys/RIOT,smlng/RIOT,kaspar030/RIOT,toonst/RIOT,mtausig/RIOT,josephnoir/RIOT,ant9000/RIOT,kaspar030/RIOT,ant9000/RIOT,aeneby/RIOT,x3ro/RIOT,OlegHahm/RIOT,toonst/RIOT,OTAkeys/RIOT,mtausig/RIOT,kaspar030/RIOT,x3ro/RIOT,kaspar030/RIOT,kYc0o/RIOT,x3ro/RIOT,RIOT-OS/RIOT,miri64/RIOT,toonst/RIOT,smlng/RIOT,basilfx/RIOT,authmillenon/RIOT,basilfx/RIOT,smlng/RIOT,kYc0o/RIOT,yogo1212/RIOT,smlng/RIOT,basilfx/RIOT,josephnoir/RIOT,jasonatran/RIOT,mtausig/RIOT,basilfx/RIOT,miri64/RIOT,x3ro/RIOT,aeneby/RIOT,OTAkeys/RIOT,miri64/RIOT,smlng/RIOT,authmillenon/RIOT,OTAkeys/RIOT,toonst/RIOT,yogo1212/RIOT,jasonatran/RIOT,jasonatran/RIOT,kYc0o/RIOT,yogo1212/RIOT,basilfx/RIOT,RIOT-OS/RIOT,authmillenon/RIOT,ant9000/RIOT,authmillenon/RIOT,x3ro/RIOT,kYc0o/RIOT,authmillenon/RIOT,aeneby/RIOT,miri64/RIOT,RIOT-OS/RIOT,yogo1212/RIOT,aeneby/RIOT