efi/fb: Correct PCI_STD_RESOURCE_END usage

PCI_STD_RESOURCE_END is (confusingly) the index of the last valid BAR, not
the *number* of BARs.  To iterate through all possible BARs, we need to
include PCI_STD_RESOURCE_END.

Fixes: 55d728a4 ("efi/fb: Avoid reconfiguration of BAR that covers the framebuffer")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>