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.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>