mount: Rename proc_mountinfo mnt_root to mountpoint

What is stored there is the path to mountpoint. The root
is the field previously named "parent root".
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

include/proc_parse.h

@@ -89,7 +89,7 @@ struct proc_mountinfo {
 	int		mnt_id;
 	int		parent_mnt_id;
 	unsigned int	s_dev;
-	char		mnt_root[64];
+	char		mountpoint[64];
 };
 
 extern int parse_mountinfo(pid_t pid, struct proc_mountinfo *mi, int nr_elems);

mount.c

@@ -26,7 +26,7 @@ again:
 	for (i = last; i < nr_mntinfo; i++) {
 		if (s_dev == mntinfo[i].s_dev) {
 			last = i;
-			return open(mntinfo[i].mnt_root, O_RDONLY);
+			return open(mntinfo[i].mountpoint, O_RDONLY);
 		}
 	}
 

proc_parse.c

@@ -485,7 +485,7 @@ int parse_mountinfo(pid_t pid, struct proc_mountinfo *mi, int nr_elems)
 
 	while (fgets(str, sizeof(str), f)) {
 		unsigned int kmaj, kmin, parent_mnt_id;
-		char parent_mnt_root[63];
+		char mnt_root[63];
 		int ret;
 
 		if ((i + 1) >= nr_elems) {
@@ -495,8 +495,8 @@ int parse_mountinfo(pid_t pid, struct proc_mountinfo *mi, int nr_elems)
 
 		ret = sscanf(str, "%i %i %u:%u %63s %63s",
 			     &mi[i].mnt_id, &parent_mnt_id,
-			     &kmaj, &kmin, parent_mnt_root,
-			     mi[i].mnt_root);
+			     &kmaj, &kmin, mnt_root,
+			     mi[i].mountpoint);
 		if (ret != 6) {
 			pr_err("Bad format in %d mountinfo\n", pid);
 			i = -1;