the encoding of cv.starti may need to be updated

Created by: ChunyuLiao

[ ]+4:[ ]+5e6040ab[ ]+cv.starti[ ]+1,bd0 +<target+0xbd0>

https://github.com/openhwgroup/corev-binutils-gdb/blob/development/gas/testsuite/gas/riscv/cv-hwlp-starti.d#L11

the new spec: https://github.com/openhwgroup/cv32e40p/blob/master/docs/source/instruction_set_extensions.rst

| 31 : 20 | 19 :15 | 14 : 12 | 11 :08 | 07 | 06 : 00 | |

| uimmL[11:0] | 00000 | 100 | 0000 | L | 010 1011 | cv.starti L, uimmL |

According to the new spec, the cv.starti 1,bd0 seems to be bd, 00, 40, ab, not 5e, 60, 40, ab?