Fix RMSNorm doc rendering (pytorch#154205)

By removing `::func::` decorator which adds unneeded parenthesis

Test plan: Check https://docs-preview.pytorch.org/pytorch/pytorch/154205/generated/torch.nn.RMSNorm.html#rmsnorm
that now renders as
<img width="704" alt="image" src="https://github.com/user-attachments/assets/443f605d-75a6-41ef-8971-21e7dc8ef9f6" />

Fixes pytorch#154184

Pull Request resolved: pytorch#154205
Approved by: https://github.com/mikaylagawarecki

Author: malfet

torch/nn/modules/normalization.py

@@ -343,7 +343,7 @@ class RMSNorm(Module):
 
             If a single integer is used, it is treated as a singleton list, and this module will
             normalize over the last dimension which is expected to be of that specific size.
-        eps: a value added to the denominator for numerical stability. Default: :func:`torch.finfo(x.dtype).eps`
+        eps: a value added to the denominator for numerical stability. Default: ``torch.finfo(x.dtype).eps``
         elementwise_affine: a boolean value that when set to ``True``, this module
             has learnable per-element affine parameters initialized to ones (for weights). Default: ``True``.