Comment on RV32E register address check in compressed decoder
Comment on RV32E register address check in compressed decoder

It is not necessary to do this check in the compressed decoder. If a
compressed instruction in RV32E tries to access any register x16 - x31,
the regular decoder triggers an illegal instruction exception and the
controller writes the actual faulting (compressed) instruction to
`mtval`.

AmbiML/ibex,AmbiML/ibex,lowRISC/ibex,lowRISC/ibex,AmbiML/ibex,AmbiML/ibex,lowRISC/ibex,lowRISC/ibex