manifest: Update libmetal to latest including POSIX arch support

Update libmetal to the latest version which includes
support for the POSIX architecture.

Signed-off-by: Alberto Escolar Piedras <[email protected]>

Author: aescolar

west.yml

@@ -257,7 +257,7 @@ manifest:
       groups:
         - hal
     - name: libmetal
-      revision: b91611a6f47dd29fb24c46e5621e797557f80ec6
+      revision: 03140d7f4bd9ba474ebfbb6256e84a9089248e67
       path: modules/hal/libmetal
       groups:
         - hal