mmc: core: Remove disabling of clk-gating for sdio cards

This removes disabling of clock-gating for qca6574
& qca9377. Now since async card interrupt support for
sdio card has been added(3c5351c0643a), re-enable
clk-gating support for sdio cards.

Change-Id: Ib497556f10c9c6576a3e0a3592f6755c8725370c
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>