ARM: dts: msm: Remove mtp and cdp dtsi files for sm6150

MTP and CDP platforms are not present for sm6150. These two
files got missed when we removed the mtp and cdp support.
Delete the dtsi files of mtp and cdp.

Change-Id: I2eda7e8733b25d751a40807bee8a641d773e7ee9
Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>