This patch adds SDHCI_QUIRK_INVERTED_WRITE_PROTECT quirk. When
specified, the sdhci driver will invert WP state.

p.s. Actually, the quirk is more board-specific than
     controller-specific.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>