ARM: dts: msm: Don't set reset-bam-on-disconnect for msm8940/8952

As the sequence to disconnect BAM2BAM pipes is changed for platforms
having USB2 controller and IPA hardware, it is not required to reset USB
BAM after pipes are disconnected. Hence remove the reset-bam-on-disconnect
property for msm8940 and msm8952.

Change-Id: I9f567d0e73e752e44305be8a53da4d2811eb40ab
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>