frudevice: change timeformat to %Y-%m-%d - %H:%M:%S

Change the time format to match the specification in the
xyz.openbmc_project.Inventory.Decorator.Asset interface.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I8ae617592170db189b23bad8c39567d29cfb41e5
diff --git a/src/FruDevice.cpp b/src/FruDevice.cpp
index d4fbc0b..10750cf 100644
--- a/src/FruDevice.cpp
+++ b/src/FruDevice.cpp
@@ -736,7 +736,7 @@
                 // Tue Nov 20 23:08:00 2018
                 char timeString[32] = {0};
                 auto bytes = std::strftime(timeString, sizeof(timeString),
-                                           "%a %b %e %H:%M:%S %Y", &fruTime);
+                                           "%Y-%m-%d - %H:%M:%S", &fruTime);
                 if (bytes == 0)
                 {
                     std::cerr << "invalid time string encountered\n";