Do not change origin of multifile class bridges to something else
because, as it turns out, there are numerous origin-specific checks in
the codegen that start to behave differently for multifile bridges.
Instead of the method-targeted origin MULTIFILE_BRIDGE, use new class
origin JVM_MULTIFILE_CLASS to detect whether a declaration is a
multifile bridge.
#KT-40198 Fixed
#KT-43145 Fixed
Alexander Udalov