PCI/DPC: Squash dpc_rp_pio_get_info() into dpc_process_rp_pio_error()

dpc_process_rp_pio_error() only calls dpc_rp_pio_get_info(), so squash them
together.  No functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sinan Kaya <okaya@codeaurora.org>