Fix: enable-rotation: wrong type of rotation specified in message

Fix: enable-rotation: wrong type of rotation specified in message

48a4000 changed the initialization of the schedule_type_str to allow the
code to compile as C++. The C-version of the code explicitly specified
the enum values which was "safer" while the C++ version assumes that the
array is initialized in the order of the enum's values.

This results in an incorrect message when enabling a rotation schedule.
For instance, enabling a periodic rotation will print that a
"size-based" rotation was successfully enabled.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I3cb6fcb6a67d7b0fa4c7913694923b5f03255389