When reading 32 bits a 32-bit shift would be executed.
This is undefined behaviour, but in this case we can just replace the
entire scratch value to avoid it.
Differential Revision: https://reviews.llvm.org/D110769
M68kDisassembler should put M68kDesc as its direct library dependency
since it uses logics releated to code beads Otherwise the build will
fail when building LLVM libraries as shared objects (building LLVM
libraries statically won't have this problem though)
Ricky Taylor