Avoid "Error from statvfs2" showing reaptedly.

Add check Storage or Inode path whether exist in the system.
Fixes openbmc/phosphor-health-monitor#1.

Signed-off-by: Bruce Lee <Bruce_Lee@quantatw.com>
Change-Id: Iff298615c59324c1d9907261d124b69a7b94e233
1 file changed