ARM: dts: msm: Increase USB QMP PHY register address space size on MSM8996

Currently used USB QMP PHY register address space size is 0x45c which is
used by Linux USB QMP PHY driver to memory mapped the region. Some of
QMP PHY registers' read/write offset is above this size. Hence increase
USB QMP PHY register address space size to 0x7a8 to memory map complete
USB QMP PHY related register address space.

CRs-Fixed: 992231
Change-Id: I2a861c6a0d34d75aaad508b182c4007b6b448c2e
Signed-off-by: Mayank Rana <mrana@codeaurora.org>