btrfs-progs: include headers required for musl-libc

This fixes various compilation errors where PATH_MAX and XATTR_SIZE_MAX
were missing. To my knowledge, this should have no bad side effects.

Signed-off-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: David Sterba <dsterba@suse.cz>

btrfs-convert.c

@@ -31,6 +31,7 @@
 #include <fcntl.h>
 #include <unistd.h>
 #include <uuid/uuid.h>
+#include <linux/limits.h>
 
 #include "ctree.h"
 #include "disk-io.h"

help.c

@@ -17,6 +17,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <limits.h>
 
 #include "commands.h"
 #include "utils.h"

mkfs.c

@@ -35,6 +35,8 @@
 #include <uuid/uuid.h>
 #include <ctype.h>
 #include <sys/xattr.h>
+#include <limits.h>
+#include <linux/limits.h>
 #include <blkid/blkid.h>
 #include <ftw.h>
 #include "ctree.h"