clock-gcc-8994: Associate reset with gcc_usb3_phy_pipe_clk

A standalone reset was provided for USB3PHY_PHY_BCR. Associate it
with gcc_usb3_phy_pipe_clk instead to keep it consistent with other
targets.

Change-Id: I9fe5965f59e8dff1e30967ecd9872054d5a48c52
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>