oeqa/core/loader: Fix filtering on test modules with submodules
Our filtering allows to specify which tests to run using,
<module_name>.[test_class].[test_name]
But the module name logic was restricted to only accept one level,
for example: runtime_test vs oelib.types, to support multiple
submodules use only the first part for filtering.
This allows to run the whole tests in a module with more than tree
levels.
Due to the ambiguity on the test filtering options with test cases
with more than tree levels the supported sytnax is,
<module>
or
<module>.[submoduleN].[test_class].[test_name]
[YOCTO #11632]
Signed-off-by: Aníbal Limón <anibal.limon@linux.intel.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
