PCI: rcar: Depend on ARCH_RENESAS, not ARCH_SHMOBILE
Make the R-Car drivers depend on ARCH_RENESAS instead of ARCH_SHMOBILE.
This is part of an ongoing process to migrate from ARCH_SHMOBILE to
ARCH_RENESAS. The motivation is that RENESAS seems to be a more
appropriate name than SHMOBILE for the majority of Renesas ARM-based SoCs.