Fix generate syscall header script: add missing escape char

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
lttng-get-syscall-inout.sh depends on bash

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
syscall tracing: input/output parameter handling for all arch

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>