edac_mc: Cleanup per-dimm_info debug messages

The edac_mc_alloc() routine allocates one dimm_info device for all
possible memories, including the non-filled ones. The debug messages
there are somewhat confusing. So, cleans them, by moving the code
that prints the memory location to edac_mc, and using it on both
edac_mc_sysfs and edac_mc.

Also, only dumps information when DIMM/ranks are actually
filled.

After this patch, a dimm-based memory controller will print the debug
info as:

[ 1011.380027] EDAC DEBUG: edac_mc_dump_csrow: csrow->csrow_idx = 0
[ 1011.380029] EDAC DEBUG: edac_mc_dump_csrow:   csrow = ffff8801169be000
[ 1011.380031] EDAC DEBUG: edac_mc_dump_csrow:   csrow->first_page = 0x0
[ 1011.380032] EDAC DEBUG: edac_mc_dump_csrow:   csrow->last_page = 0x0
[ 1011.380034] EDAC DEBUG: edac_mc_dump_csrow:   csrow->page_mask = 0x0
[ 1011.380035] EDAC DEBUG: edac_mc_dump_csrow:   csrow->nr_channels = 3
[ 1011.380037] EDAC DEBUG: edac_mc_dump_csrow:   csrow->channels = ffff8801149c2840
[ 1011.380039] EDAC DEBUG: edac_mc_dump_csrow:   csrow->mci = ffff880117426000
[ 1011.380041] EDAC DEBUG: edac_mc_dump_channel:   channel->chan_idx = 0
[ 1011.380042] EDAC DEBUG: edac_mc_dump_channel:     channel = ffff8801149c2860
[ 1011.380044] EDAC DEBUG: edac_mc_dump_channel:     channel->csrow = ffff8801169be000
[ 1011.380046] EDAC DEBUG: edac_mc_dump_channel:     channel->dimm = ffff88010fe90400
...
[ 1011.380095] EDAC DEBUG: edac_mc_dump_dimm: dimm0: channel 0 slot 0 mapped as virtual row 0, chan 0
[ 1011.380097] EDAC DEBUG: edac_mc_dump_dimm:   dimm = ffff88010fe90400
[ 1011.380099] EDAC DEBUG: edac_mc_dump_dimm:   dimm->label = 'CPU#0Channel#0_DIMM#0'
[ 1011.380101] EDAC DEBUG: edac_mc_dump_dimm:   dimm->nr_pages = 0x40000
[ 1011.380103] EDAC DEBUG: edac_mc_dump_dimm:   dimm->grain = 8
[ 1011.380104] EDAC DEBUG: edac_mc_dump_dimm:   dimm->nr_pages = 0x40000
...

(a rank-based memory controller would print, instead of "dimm?", "rank?"
 on the above debug info)

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c
index eace646..7079a42 100644
--- a/drivers/edac/edac_mc_sysfs.c
+++ b/drivers/edac/edac_mc_sysfs.c
@@ -485,17 +485,8 @@
 				     struct device_attribute *mattr, char *data)
 {
 	struct dimm_info *dimm = to_dimm(dev);
-	struct mem_ctl_info *mci = dimm->mci;
-	int i;
-	char *p = data;
 
-	for (i = 0; i < mci->n_layers; i++) {
-		p += sprintf(p, "%s %d ",
-			     edac_layer_name[mci->layers[i].type],
-			     dimm->location[i]);
-	}
-
-	return p - data;
+	return edac_dimm_info_location(dimm, data, PAGE_SIZE);
 }
 
 static ssize_t dimmdev_label_show(struct device *dev,