TPC is only used to access the option `ShouldEmitDebugEntryValues`.

Many of these are indexing BitVectors or something where we can't
using MCRegister and need the register number.

Identified with misc-include-cleaner.

This patch handles virtual registers in the VarLocBasedImpl of the
LiveDebugVariables pass, allowing it to be used on architectures that
depend on virtual registers in debugging, like NVPTX. It enables the
pass for NVPTX.

These would implicitly cast the register to `unsigned`. Switch most of
them to use printReg will give a more readable output. Change some
others to use Register::id() so we can eventually remove the implicit
cast to `unsigned`.

Follows
https://github.com/llvm/llvm-project/pull/74682#issuecomment-1850268782.
Fixes #74680.