Syntax is

crtools exec -t <pid> <syscall_name> [<arguments>]

Two types of arguments are supported -- plain, treated
as number, passed as is to the syscall. Buffer, started
with '&' -- the rest of the string is pushed to the tgt
task's memory and pointer to one is passed as syscall
argument.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>