ISACOV : No rs1 for c.mv & c.add instructions

Created by: AyoubJalali

Hello, @MikeOpenHWGroup @silabs-robin Always in isacov, I notice that there some cover group like, cp_rs1_toggle & cp_rs1_value in c.mv & c.add instructions, but these instructions don't use rs1, so it's better to remove these cover group, and also in c_has_rs1 typedef should be reviewed https://github.com/openhwgroup/core-v-verif/blob/383dbc81f2292a785c05bea8125d157f42aa8db5/lib/uvm_agents/uvma_isacov/uvma_isacov_tdefs.sv#L559 & https://github.com/openhwgroup/core-v-verif/blob/383dbc81f2292a785c05bea8125d157f42aa8db5/lib/uvm_agents/uvma_isacov/uvma_isacov_tdefs.sv#L561