kdb: Fix breakpoint enable to be silent if already enabled

Fix the breakpoint enable command (be) to a logic that is inline with the
breakpoint disable command (bd) in which if the breakpoint is already in
an enabled state, do not print the message of enabled again to the user.

Also a small nit fix of the new line in a separate print.

Signed-off-by: Nir Lichtman <nir@lichtman.org>
Link: https://lore.kernel.org/r/20241027204729.GA907155@lichtman.org


Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>