sm-notify command: use static function definitions

Clean up.

The sm-notify command is built from a single source file.
Some of its internal functions are appropriately defined as static.

However, some are declared static, but defined as global.  Some are
declared and defined as global.  None of them are used outside of
utils/statd/sm-notify.c.

Make all the internal functions in utils/statd/sm-notify.cstatic.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steve Dickson <steved@redhat.com>