mmc: zynq_sdhci: Dll reset only for ZynqMP platform

mmc: zynq_sdhci: Dll reset only for ZynqMP platform

Dll reset is needed only for ZynqMP platforms, add condition in tuning
to call arasan_zynqmp_dll_reset() just for ZynqMP platforms.

On other platforms like Versal NET, If this condition is not added, we
see PLM error messages when dll reset smc is called.

Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@amd.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/d673ff3bdc5c236a7f0403c920e719684abd6059.1688991117.git.michal.simek@amd.com