ARM: dts: msm: add property to identify DSB TPDM for msm8998

Add device-tree property to identify for all TPDM's with DSB
dataset. The property will be used to apply MSR config to DSB
after setting the enable bit.

Change-Id: I0451b29080ab8f671cacd63d630dd31a6cb2bbb2
Signed-off-by: Satyajit Desai <sadesai@codeaurora.org>