Emit C++ accessors with "alwaysinline"

I was hoping this would work around a LLVM optimizer bug related to
calling functions (the one that currently breaks chisel_cat-64-1), but
it doesn't appear to have actually helped any.  In fact, it doesn't
appear to actually do anything at all -- LLVM still emits those
function calls.

I'm thinking it's a problem related to trying to optimize C++ and IR
together, but I'm not 100% sure about that.