mmc: sdhci_pltfm: pass more data on custom init call

mmc: sdhci_pltfm: pass more data on custom init call

The custom init call may need more data to perform its job, so we pass
it a pointer to pdata, too. Also, always use the platform_id specific
data even if platform_data is present. Doing that, platform_data can
additionally be parsed by init() for board-specific information (via
sdhci->mmc->parent).

(Note: the old behaviour was that you could override the platform_id
specific data with your own. However, one can still do this by using the
"sdhci" id instead of "sdhci-<something>".)

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Chris Ball <cjb@laptop.org>