py/modcollections: Rename module name have "u" prefix for consistency.
diff --git a/py/objmodule.c b/py/objmodule.c
index 7d5ba4e..8c3cb85 100644
--- a/py/objmodule.c
+++ b/py/objmodule.c
@@ -140,7 +140,7 @@
     { MP_ROM_QSTR(MP_QSTR_uio), MP_ROM_PTR(&mp_module_io) },
 #endif
 #if MICROPY_PY_COLLECTIONS
-    { MP_ROM_QSTR(MP_QSTR__collections), MP_ROM_PTR(&mp_module_collections) },
+    { MP_ROM_QSTR(MP_QSTR_ucollections), MP_ROM_PTR(&mp_module_collections) },
 #endif
 #if MICROPY_PY_STRUCT
     { MP_ROM_QSTR(MP_QSTR_ustruct), MP_ROM_PTR(&mp_module_ustruct) },