ARM: dts: msm: Fix hsic vddcx supply name in apq8084

Replace incorrect supply name hsic_vdd_dig with hsic-vdd-dig
supply name so that hsic driver can successfully get the
regulator handle.

Change-Id: I07fc42ad4eb8ce02cabfce2ae08451bc8cfb9703
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>