ARM: dts: msm: separate jtagv8-mm device tree changes for msm8996

Some of the workarounds for saving and restoring of ETM registers
are not applicable for MSM8996 V3. Separate version specific
device tree changes for ETM registers.

Change-Id: I125cc107dc443b49d52e76af030faf6aa4201432
Signed-off-by: Sarangdhar Joshi <spjoshi@codeaurora.org>