Revert "Fix compilation with debugfs disabled"

This reverts commit f8123a7e0d87277bb39769abb173f2ec20cf4aba.
Revert "Fix compilation with debugfs disabled"

This reverts commit b83ca50de85932e165814124b5b2690361dfbf52.
Revert "debug_mm: Only print pr_debug and pr_info if DEBUG."

This reverts commit 01ff2e3b246a4370ecdccba4e0a882a35e1e2a5b.