ARM: dts: msm: Avoid Tx FIFO resizing on secondary USB core for SM6150

Secondary USB controller on SM6150 has the maximum speed as high.
Tx FIFO resizing is not required for it and default programming
is good enough. Hence, remove the flag 'tx-fifo-resize'.

Change-Id: I3073cdc0eb61b2c1a3c5b15bf5866f33cb755e71
Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>