fsl_esdhc: Update clock enable bits for USDHC

The USDHC moves the 4 clock bits CARD_CLK_SOFT_EN, IPG_PERCLK_SOFT_EN,
HCLK_SOFT_EN, and IPG_CLK_SOFT_EN from sysctl register to vendorspec
register. The driver uses RSTA to replace the clock gate off
operation. But this is not a good solution because:
1. when using RSTA, we should wait this bit to clear by itself. This is not
   implemeneted in the code.
2. After RSTA is set, it is recommended that the Host Driver reset the
   external card and reinitialize it.

So in this patch, we change to use the vendorspec registers for these bits
operation.

Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: York Sun <york.sun@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>