Pass -Og to EXTRA_CFLAGS as well as to CFLAGS_NODIST
    
     - to CFLAGS_NODIST to take precedence as CFLAGS_NODIST go after EXTRA_CFLAGS
     - to EXTRA_CFLAGS to "bake it in" and build extension modules with -Og
     - call make regen-all with the same flags, as it invokes gcc as well