Don't morph volatile IND(ADDR(LCL_VAR)) (dotnet/coreclr#20843)

Don't morph volatile IND(ADDR(LCL_VAR)) (dotnet/coreclr#20843)

Besides the fact that volatile indirections aren't supposed to be removed doing so in this case results in incorrect code being generated.

The GT_IND node has GTF_DONT_CSE set and this gets copied to the GT_LCL_VAR node. Later this prevents the insertion of a normalization cast because GTF_DONT_CSE on a GT_LCL_VAR node is assumed to mean that the variable address is being taken.

Commit migrated from https://github.com/dotnet/coreclr/commit/3e216841102ab82a6f4b276aadd8558d78819c12