build: criu -- Drop redundant phonies

Everytime we build the executable we've to check
all the deps and sources for changes, thus
don't protvide criu/criu on toplevel as
a target file (my bug in 496b51b6).

Instead bring this target as a phony back
but drop phony from criu/Makefile itself,
as it should be from the beginning.

Same time remove unneeded phonies over
the targets which are real files.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Tested-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>