Rename getPSUInventoryPath to getPSUInventoryPaths

Rename the utils method/function getPSUInventoryPath() to
getPSUInventoryPaths().  The method/function returns multiple paths in a
vector, so the name should be plural.  This will make the return type
more clear.  Currently the name implies only one path will be returned.

Tested:
* Verified all automated tests build and run successfully
* Verified getPSUInventoryPaths() returns correct data

Change-Id: I7e215c37e3ce1eb27313bc51348c7f7335c8f67a
Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
diff --git a/test/test_utils.cpp b/test/test_utils.cpp
index 114b93a..d12e1f3 100644
--- a/test/test_utils.cpp
+++ b/test/test_utils.cpp
@@ -57,7 +57,7 @@
     EXPECT_CALL(sdbusMock, sd_bus_message_exit_container(IsNull()))
         .WillOnce(Return(0)); /* end of std::vector */
 
-    auto ret = utils::getPSUInventoryPath(bus);
+    auto ret = utils::getPSUInventoryPaths(bus);
     EXPECT_EQ(2U, ret.size());
     EXPECT_EQ(path0, ret[0]);
     EXPECT_EQ(path1, ret[1]);