mmc: host: sdhci-msm: Don't clear IO_PAD_PWR_SWITCH when faking 3V support

Don't clear io pad power switch setting when 3V support is faked.
This bit has to be cleared for allowing IO pad to switch to 3V when
Vccq is really configured to 3V. But in case of faking 3V where we
configure Vccq to 1.8V only, we shouldn't clear this bit.

Change-Id: I15c7e3f49703c3ac31d59d7d4bfbd81f3c2dc028
Signed-off-by: Sarthak Garg <sartgarg@codeaurora.org>