loading: rm no-op conditional in cache rejection (#60150)

Introduced in #55992 - looks like
rebase mistake, the actually operating condition is equivalent modulo
the extra readabilitycheck.

Author: Keno

base/loading.jl

@@ -4232,7 +4232,6 @@ end
                 # file before comparing it with `modpath`.
                 stdlib_path = fixup_stdlib_path(includes[1].filename)
                 if !(isreadable(stdlib_path) && samefile(stdlib_path, modpath))
-                    !samefile(fixup_stdlib_path(includes[1].filename), modpath)
                     @debug "Rejecting cache file $cachefile because it is for file $(includes[1].filename) not file $modpath"
                     record_reason(reasons, "different source file path")
                     return true # cache file was compiled from a different path