[llvm] [AMDGPU] Account for inline asm size in inst_pref_size calculation (PR #192306)

[Stanislav Mekhanoshin via llvm-commits]

rampitec wrote:

> @rampitec do you want to re-review the patch since a lot has changed since you approved it?

Still LGTM.

https://github.com/llvm/llvm-project/pull/192306