Correct error message printed when the 'chosen_drive' cannot be added.

Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>

Assemble.c

@@ -610,7 +610,7 @@ This doesnt work yet
 						devices[j].devname,
 						mddev,
 						strerror(errno));
-					if (i < first_super.raid_disks)
+					if (i < first_super.raid_disks || i == bestcnt)
 						okcnt--;
 					else
 						sparecnt--;

ChangeLog

@@ -15,6 +15,8 @@ Changes Prior to 1.9.0 release
 	it to find devices, rather than only once.
     -   Make "mdadm -Ss" stop stacked devices properly, by reversing the
 	order in which arrays are stopped.
+    -   Correct error message when last device to be added to an array
+        fails.
 
 Changes Prior to 1.8.0 release
     -   Makefile cleanup from  Luca Berra <bluca@comedia.it>