Fix real path vs symlink inconsistence

When calling abspath on a filename, the function returns its canonical
(real) path. In our tests, this value is compared against a symlink,
which causes errors.

fusesoc/config.py

@@ -103,7 +103,7 @@ def _resolve_path_from_cfg(self, path):
         if os.path.isabs(expanded):
             return expanded
         else:
-            cfg_file_dir = os.path.dirname(os.path.abspath(self._path))
+            cfg_file_dir = os.path.dirname(os.path.realpath(self._path))
             return os.path.normpath(os.path.join(cfg_file_dir, expanded))
 
     def _path_from_cfg(self, name):

fusesoc/coremanager.py

@@ -286,7 +286,7 @@ def find_cores(self, library, ignored_dirs):
         visited = set()
         for root, dirs, files in os.walk(path, followlinks=True):
             ignore_tree = ("FUSESOC_IGNORE" in files) or (
-                os.path.abspath(root) in ignored_dirs
+                os.path.realpath(root) in ignored_dirs
             )
             if ignore_tree:
                 del dirs[:]

tests/test_config.py

@@ -88,7 +88,7 @@ def test_config_relative_path():
 
         conf = Config(tcf.name)
         for name in ["build_root", "cache_root", "library_root"]:
-            abs_td = os.path.abspath(td)
+            abs_td = os.path.realpath(td)
             assert getattr(conf, name) == os.path.join(abs_td, name)
 
 
@@ -107,7 +107,7 @@ def test_config_relative_path_starts_with_dot():
 
         conf = Config(tcf.name)
         for name in ["build_root", "cache_root", "library_root"]:
-            abs_td = os.path.abspath(td)
+            abs_td = os.path.realpath(td)
             assert getattr(conf, name) == os.path.join(abs_td, name)
 
 
@@ -128,7 +128,7 @@ def test_config_relative_path_with_local_config():
 
         conf = Config(tcf.name)
         for name in ["build_root", "cache_root", "library_root"]:
-            abs_td = os.path.abspath(td)
+            abs_td = os.path.realpath(td)
             assert getattr(conf, name) == os.path.join(abs_td, name)
     os.chdir(prev_dir)