spi: spi-zynq-gqspi: Set appropriate tapdelay during driver initialization

commit  0e8b17b82a9116ef7dfbd1fb15fa11d195cf116c from
https://github.com/Xilinx/linux-xlnx.git xlnx_rebase_v5.10

Driver calculates the baud rate value during hardware initialization,
without setting spi clock frequency to the max speed(i.e., ref_clk/2).
This results in setting wrong tapdelay values.
This error was introduced by:
'commit 1c26372e

 ("spi: spi-zynqmp-gqspi: Update driver to use spi-mem
framework")'

This patch fixes the issue by initializing spi clock frequency, before
calling hardware initialization api.

Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@xilinx.com>
State: pending
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>