mmc: sdhci-pci: Tidy o2micro definitions

We keep PCI Ids in sdhci-pci.h and the O2-specific definitions belong in
sdhci-pci-o2micro.c. Move those definitions accordingly. Remove unused O2
definitions in sdhci-pci-core.c. The 3 o2micro external function
declarations might as well be in sdhci-pci.h as well, so move them there
and get rid of sdhci-pci-o2micro.h entirely.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>