PCI: ibmphp: Remove unneeded break

A break is not needed if it is preceded by a return.

Based on Tom Rix's treewide patch; this instance extracted from Joe
Perches' list.

Link: https://lore.kernel.org/r/20201017160928.12698-1-trix@redhat.com
Link: https://lore.kernel.org/r/f530b7aeecbbf9654b4540cfa20023a4c2a11889.camel@perches
.com
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Tom Rix <trix@redhat.com>
Cc: Joe Perches <joe@perches.com>