In PG2.0 there is an issue where PHY's FDSP Code RAM sometimes gets
corrupted when exiting from ELP mode. This issue is related to FDSP
Code RAM clock implementation.

PG2.1 introduces a HW fix for this issue that requires the driver to
change the FDSP Code Ram clock settings (mux it to ATGP clock instead
of its own clock).

This workaround uses PHY_FPGA_SPARE_1 register and is relevant to WL8
PG2.1 devices.

The fix is also backward compatible with older PG2.0 devices where the
register PHY_FPGA_SPARE_1 is not used and not connected.

The fix is done in the wl18xx_pre_upload function (must be performed
before uploading the FW code) and includes the following steps:

1. Disable FDSP clock
2. Set ATPG clock toward FDSP Code RAM rather than its own clock.
3. Re-enable FDSP clock
Signed-off-by: Yair Shapira <yair.shapira@ti.com>
Signed-off-by: Ido Reis <idor@ti.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>