This patch adds the appropriate macros, tests and codec entries to encode the following variants:
ADDPL <Xd|SP>, <Xn|SP>, #<imm>
ADDVL <Xd|SP>, <Xn|SP>, #<imm>
RDVL <Xd>, #<imm>Support for ADR instructions will be added in a later commit.
Issues: #3044