[clang] [Driver] Teach Barmetal toolchain about GCC installation (PR #121829)

[Garvit Gupta via cfe-commits]

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@@ -79,7 +87,6 @@ class LLVM_LIBRARY_VISIBILITY BareMetal : public ToolChain {
   OrderedMultilibs getOrderedMultilibs() const;
 
   std::string SysRoot;
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quic-garvgupt wrote:

Removing this private variable was making the code messy because there have been updates to this variable in some member functions and the updated value is then further used in other functions.  Removing this variable would need to pass this as an argument to all those functions which would make the code less readable.

To avoid the confusion, all local variables for sysroot are named as `SysRootDir` and any references to this variable as `SysRoot` only

https://github.com/llvm/llvm-project/pull/121829