[llvm] [AMDGPU] Fix hidden kernarg preload count inconsistency (PR #116759)

[Matt Arsenault via llvm-commits]

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@@ -1692,11 +1694,12 @@ class GCNUserSGPRUsageInfo {
     KernargSegmentPtrID = 4,
     DispatchIdID = 5,
     FlatScratchInitID = 6,
-    PrivateSegmentSizeID = 7
+    PrivateSegmentSizeID = 7,
+    LDSKernelIdID = 8
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arsenm wrote:

Comment this isn't really a user SGPR? Maybe should rename the enum 

https://github.com/llvm/llvm-project/pull/116759