spmi: Remove shutdown/suspend/resume kernel-doc

These members of the driver structure are not present.
Remove them from the kernel-doc.

Cc: Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>