[PATCH] ppc64: use newer RTAS call when available

[PATCH] ppc64: use newer RTAS call when available

This patch is from Nathan Fontenot <nfont@austin.ibm.com> originally.

The PPC64 EEH code needs a small update to start using the
ibm,read-slot-reset-state2 rtas call if available.  The currently used
ibm,read-slot-reset-state call will be going away on future machines.

This patch attempts to use the newer rtas call if available and falls back
the older version otherwise.  This will maintain EEH slot checking
capabilities on all future and current firmware levels.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>