This patch adds the instruction definitions and assembly/disassembly tests for the following set of instructions:
- Vector Extract [byte | half | word | doubleword | quad] with mask
- Vector Expand [byte | half | word | doubleword | quad] with mask
- Move to VSR [byte | byte immediate | half | word | doubleword | quad] with mask
- Vector Count Mask Bits [byte | half | word | doubleword]