edac: mpc85xx fix bad page calculation

Commit b4846251727a38a7f248e41308c060995371dd05 ("edac: mpc85xx add
mpc83xx support") accidentally broke how a chip select's first and last
page addresses are calculated. The page addresses are being shifted too
far right by PAGE_SHIFT. This results in errors such as:

EDAC MPC85xx MC1: Err addr: 0x003075c0
EDAC MPC85xx MC1: PFN: 0x00000307
EDAC MPC85xx MC1: PFN out of range!
EDAC MC1: INTERNAL ERROR: row out of range (4 >= 4)
EDAC MC1: CE - no information available: INTERNAL ERROR

The vaule of PAGE_SHIFT is already being taken into consideration during
the calculation of the 'start' and 'end' variables, thus it is not
necessary to account for it again when setting a chip select's first and
last page address.

Signed-off-by: Peter Tyser <[e-mail]>
Signed-off-by: Doug Thompson <[e-mail]>
Cc: Ira W. Snyder <[e-mail]>
Cc: Kumar Gala <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/edac/mpc85xx_edac.c

···
 		end   <<= (24 - PAGE_SHIFT);
 		end    |= (1 << (24 - PAGE_SHIFT)) - 1;
 
-		csrow->first_page = start >> PAGE_SHIFT;
-		csrow->last_page = end >> PAGE_SHIFT;
+		csrow->first_page = start;
+		csrow->last_page = end;
 		csrow->nr_pages = end + 1 - start;
 		csrow->grain = 8;
 		csrow->mtype = mtype;