mmc: ignore CRC errors from CMD13 (status) when changing rates

Update mmc_switch_status to ignore a few CRC errrors when asking for the
card status after setting the new rate with CMD6. Since the card may
take a little while to make the switch, it's possible we'll get a
communications error if we sent the command at the wrong time. Several
low end laptops needs this workaround as they have a window that seems
longer than other systems. This is known to fix at least the Acer Aspire
A114-32-P7E5.

Reviewed by: imp@, manu@
Differential Revision: https://reviews.freebsd.org/D24740