effects: handle va-method properly when refining `:inaccessiblememonly` (#48854)
Previously the `:inaccessiblememonly` effect bit may be wrongly refined
when analyzing va-method, e.g.:
```julia
julia> callgetfield1(xs...) = getfield(getfield(xs, 1), 1)
callgetfield1 (generic function with 1 method)
julia> Base.infer_effects(callgetfield1, (Base.RefValue{Symbol},))
(+c,+e,!n,+t,+s,+m,+i) # inaccessiblememonly is wrongly refined here
```
This leads to wrong concrete evaluation of `callgetfield1` and thus may
result in a problem like below:
```julia
julia> const GLOBAL_XS = Ref(:julia);
julia> global_getfield() = callgetfield1(GLOBAL_XS);
julia> @test let
Base.Experimental.@force_compile
global_getfield()
end === :julia
Test Passed
julia> GLOBAL_XS[] = :julia2;
julia> @test let
Base.Experimental.@force_compile
global_getfield()
end === :julia2 # this fails
Test Failed at REPL[8]:1
Expression: let
#= REPL[8]:2 =# Base.Experimental.@force_compile
global_getfield()
end === :julia2
Evaluated: julia === julia2
```
This commit fixes it up.
julia
903dbd5f - effects: handle va-method properly when refining `:inaccessiblememonly` (#48854)
