Refactor Version::getValue()

Rename the function to getValues() and change the parameter and return
value types, and add a test case for it.
It will be used in future commits.

Tested: Verify the unit test case passes.

Signed-off-by: Lei YU <mine260309@gmail.com>
Change-Id: I57ccf857737ef13f4e2f27c5f2fb7400a2170e91
diff --git a/test/meson.build b/test/meson.build
index 0b7b217..2de2b21 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -44,6 +44,7 @@
   '../src/version.cpp',
   'test_item_updater.cpp',
   'test_activation.cpp',
+  'test_version.cpp',
   include_directories: [psu_inc, test_inc],
   link_args: dynamic_linker,
   build_rpath: oe_sdk.enabled() ? rpath : '',