mmc: esdhc: set the timeout to the max value

When accessing the card on some FSL platform boards (e.g p2020, p1010,
mpc8536), the following error is reported with the timeout value calculated:

mmc0: Got data interrupt 0x00000020 even though no data operation was
in progress.
mmc0: Got data interrupt 0x00000020 even though no data operation was
in progress.

So we skip the calculation of timeout and use the max value to fix it.

Signed-off-by: Jerry Huang <Chang-Ming.Huang@freescale.com>
Signed-off-by: Gao Guanhua <B22826@freescale.com>
Signed-off-by: Xie Xiaobo <X.Xie@freescale.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>