[0/1] RISC-V: Update CSR to priv 1.11.

[Nelson Chu]

Hi gdb,

Since RISCV priv spec 1.11 has been officially released, it would be good if
binutils, gdb, qemu and OpenOCD can support the new CSR.  Therfore, I update
the CSR to 1.11 in binutils, and the gdm xml files and gas/testsuite/gas/riscv/csr-dw-regnums
also need to be updated.  There are two difference between 1.10 and 1.11,

1. 0x320 is mcountinhibit rather than mucounteren.  You can still use the
   mucounteren, but objdump will show mcountinhibit for it.

2. 0x7b2 is dscratch0 rather than dscratch, and 0x7b3 is dscratch1.  You
   can still use the old naming, but objdump will show the new one.

Thanks
Nelson