scripts/lib/compatlayer: detect_layers always use realpath's

If you are using relative paths and change to other folder for
execution it will fail, so use realpaths always.

[YOCTO #11164]

(From OE-Core rev: 14283700f8ec9dcb29cbc00c92d76173f1601bf5)

Signed-off-by: Aníbal Limón <anibal.limon@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/lib/compatlayer/__init__.py

@@ -112,6 +112,7 @@ def detect_layers(layer_directories, no_auto):
     layers = []
 
     for directory in layer_directories:
+        directory = os.path.realpath(directory)
         if directory[-1] == '/':
             directory = directory[0:-1]