Provide CreateValueFromData,Expression at the SBTarget level as well as the SBValue level; and also make all the implenentations agree on using the matching ValueObject::Create instead of doing code copypastas

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@224460 91177308-0d34-0410-b5e6-96231b3b80d8