The Zvamo and Zvlsseg should be included in the base V extension.

Treat the architecture string "v_zvamo_zvlsseg" and "v" as the same.
That is, you only need to enable V extension, then the vector AMO
and vector load/store segment instructions are also enabled.

Beside, rename INSN_CLASS_V_AND_ZV* to INSN_CLASS_ZV*, this simplify
the naming of subsets.