aarch64: Eliminate AARCH64_OPND_SVE_ADDR_R
Adjust parsing for AARCH64_OPND_SVE_ADDR_RR{_LSL*} operands to accept
implicit XZR offsets. Add new AARCH64_OPND_SVE_ADDR_RM{_LSL*} operands
to support instructions where an XZR offset is allowed but must be
specified explicitly. This allows the removal of the duplicate opcode
table entries using AARCH64_OPND_SVE_ADDR_R.