[GFS2] Extended attribute code style changes

As per Jan Engelhardt's request and also a few of my own. It has
been possible to add a few most const to the code as a result of
the change in gfs2_ea_name2type.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/eaops.c b/fs/gfs2/eaops.c
index 3b8749c..adb898c 100644
--- a/fs/gfs2/eaops.c
+++ b/fs/gfs2/eaops.c
@@ -31,22 +31,22 @@
  * Returns: GFS2_EATYPE_XXX
  */
 
-unsigned int gfs2_ea_name2type(const char *name, char **truncated_name)
+unsigned int gfs2_ea_name2type(const char *name, const char **truncated_name)
 {
 	unsigned int type;
 
 	if (strncmp(name, "system.", 7) == 0) {
 		type = GFS2_EATYPE_SYS;
 		if (truncated_name)
-			*truncated_name = strchr(name, '.') + 1;
+			*truncated_name = name + sizeof("system.") - 1;
 	} else if (strncmp(name, "user.", 5) == 0) {
 		type = GFS2_EATYPE_USR;
 		if (truncated_name)
-			*truncated_name = strchr(name, '.') + 1;
+			*truncated_name = name + sizeof("user.") - 1;
 	} else if (strncmp(name, "security.", 9) == 0) {
 		type = GFS2_EATYPE_SECURITY;
 		if (truncated_name)
-			*truncated_name = strchr(name, '.') + 1;
+			*truncated_name = name + sizeof("security.") - 1;
 	} else {
 		type = GFS2_EATYPE_UNUSED;
 		if (truncated_name)