Nit: MCSCOCO -> MS COCO (#16481)

src/transformers/models/lxmert/modeling_lxmert.py

@@ -803,7 +803,7 @@ LXMERT_START_DOCSTRING = r"""
 
     The LXMERT model was proposed in [LXMERT: Learning Cross-Modality Encoder Representations from
     Transformers](https://arxiv.org/abs/1908.07490) by Hao Tan and Mohit Bansal. It's a vision and language transformer
-    model, pretrained on a variety of multi-modal datasets comprising of GQA, VQAv2.0, MCSCOCO captions, and Visual
+    model, pretrained on a variety of multi-modal datasets comprising of GQA, VQAv2.0, MSCOCO captions, and Visual
     genome, using a combination of masked language modeling, region of interest feature regression, cross entropy loss
     for question answering attribute prediction, and object tag prediction.