powerpc/fsl_pci: Fix sparse warnings

This patch fixes following sparse warnings:

  CHECK   fsl_pci.c
fsl_pci.c:32:13: warning: symbol 'setup_pci_atmu' was not declared. Should it be static?
fsl_pci.c:89:13: warning: symbol 'setup_pci_cmd' was not declared. Should it be static?
fsl_pci.c:133:12: warning: symbol 'fsl_pcie_check_link' was not declared. Should it be static?

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>