mmc: sdhci-sprd: drop of_match_ptr from of_device_id table

mmc: sdhci-sprd: drop of_match_ptr from of_device_id table

The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it is not relevant here).  This fixes
compile warning (!CONFIG_OF on x86_64):

    drivers/mmc/host/sdhci-sprd.c:723:34: warning:
        ‘sdhci_sprd_of_match’ defined but not used [-Wunused-const-variable=]

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Chunyan Zhang <zhang.lyra@gmail.com>
Link: https://lore.kernel.org/r/20201120162344.485921-1-krzk@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>