errinjct: Recognize -5 return from rtas
errinjct: Recognize -5 return from rtas

Update the errinjct command to recognize the rturn code of -5 from
rtas indicating that PCI error injection is not enabled.

Signed-off-by: Nathan Fontenot <4b7bfe500077bf77c5456931a34b0b70e36e0bc6@linux.vnet.ibm.com>

shenki/powerpc-utils,shenki/powerpc-utils,shenki/powerpc-utils