Uncomment and improve the implementation of compat32 support for
PT_GETDBREGS and PT_SETDBREGS requests.
The new implementation uses x86_dbregs_read() and x86_dbregs_write()
function instead of accessing pcb directly. While this might be
a little slower, it guarantees that the needed pcb field
Currently, the compat32 passes PT_* request values to kernel functions
without translation. This works fine for low PT_* requests that happen
to have the same values both on i386 and amd64. However, for requests
higher than PT_SETFPREGS, the value passed from userland (matching i386
const) does
