Add qgraph nodes for sdhci-pci and generic-sdhci (memory mapped) drivers.
Both drivers implement (produce) the same interface sdhci, that provides the
readw - readq - writeq functions.
Signed-off-by: Emanuele Giuseppe Esposito <e.emanuelegiuseppe@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>