MFC: r315431

MFC: r315431

- Adds macros for the content of SDHCI_ADMA_ERR and SDHCI_HOST_CONTROL2
  registers.
- Add slot type capability bits. These bits should allow recognizing
  removable card slots, embedded cards and shared buses (shared bus
  supposedly is always comprised of non-removable cards).
- Dump CAPABILITIES2, ADMA_ERR, HOST_CONTROL2 and ADMA_ADDRESS_LO
  registers in sdhci_dumpregs().
- The drive type support flags in the CAPABILITIES2 register are for
  drive types A,C,D, drive type B is the default setting (value 0) of
  the drive strength field in the SDHCI_HOST_CONTROL2 register.

Obtained from:	DragonFlyBSD (9e3c8f63, 455bd1b1)

git-svn-id: svn://svn.freebsd.org/base/stable/10@318200 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f