ARM: dts: msm: Add cfb_ahb_clk required in usb node for msmtitanium

It is required to add cfg_abh_clk entry from dts file for dwc3-msm
driver probe to be successful. Otherwise it will fail and leads to
USB functionaity not to be working. Hence fix this by adding the
required clock in USB device node for USB functionality to be working.

Change-Id: I4ea513b1fcfcf02e99efeac9da5c4804e5eeebfe
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>