msm: jtag: move jtag related definitions to new jtag header

Create new jtag header file and move jtag related definitions to
it. This will decouple jtag code and help make coresight code
generic.

Change-Id: I722de9945800a4d0ba5b792c1b6dda5fc0b3cc40
Signed-off-by: Pratik Patel <pratikp@codeaurora.org>