[llvm] [MC] Rename getPrivateGlobalPrefix to getInternalSymbolPrefix. NFC (PR #185164)

[Alexis Engelke via llvm-commits]

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@@ -154,9 +154,9 @@ class LLVM_ABI MCAsmInfo {
   // Do we need to create a local symbol for .size?
   bool NeedsLocalForSize = false;
 
-  /// This prefix is used for globals like constant pool entries that are
-  /// completely private to the .s file and should not have names in the .o
-  /// file.  Defaults to "L"
+  /// For internal use by compiler and assembler, not meant to be visible
+  /// externally. They are usually not emitted to the symbol table in the
+  /// object file.
   StringRef PrivateGlobalPrefix = "L";
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aengelke wrote:

Also rename variable for consistency?

https://github.com/llvm/llvm-project/pull/185164