fru: support two time string formats

Support parsing two time string formats to enable use of ipmi-fru-parser
and entity-manager to provide FRU details on dbus.

Tested: Verified the entity-manager dbus output for the FRU MfgDate is
now parsed correctly.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I053ec225b51166269c5a5a800ad8d607fd0cc233
1 file changed