msm_serial_hs_lite: Don't set UART clock to zero always

Setting UART clock rate to zero is causing multiple issues
and leading to more confusion with other stability issues.
Setting UART clock rate to zero is invalid operation on
recent platforms and throws multiple error messages. Hence
add platform data set_uart_clk_zero to enable setting uart
clock rate to zero operation on required platform for
specific use case.

Also set set_uart_clk_zero for GSBI9 shared between different
processor.

CRs-Fixed: 455466
Change-Id: Iba04d4cf094885b0eae6a9c49ed06f750bcc1024
Signed-off-by: Mayank Rana <mrana@codeaurora.org>