[AMDGPU] Update docs for nontemporal store

Update the documented GFX10 code sequence for nontemporal stores after
D114351.

Differential Revision: https://reviews.llvm.org/D114707
diff --git a/llvm/docs/AMDGPUUsage.rst b/llvm/docs/AMDGPUUsage.rst
index 0690c338..0c9de09 100644
--- a/llvm/docs/AMDGPUUsage.rst
+++ b/llvm/docs/AMDGPUUsage.rst
@@ -8677,7 +8677,7 @@
                                                          - !volatile & nontemporal
 
                                                            1. buffer/global/flat_store
-                                                              slc=1
+                                                              glc=1 slc=1
 
                                                          - volatile