btrfs-progs: Accurate errormsg for resize operation on no-enouth-free-space case

btrfs-progs: Accurate errormsg for resize operation on no-enouth-free-space case

btrfs progs output following error message when doing resize on
no-enouth-free-space case:
 # btrfs filesystem resize +10g /mnt/btrfs_5gb
 Resize '/mnt/btrfs_5gb' of '+10g'
 ERROR: unable to resize '/mnt/btrfs_5gb' - File too large
 #

It is not a good description for users, and this patch changed it to:
 # ./btrfs filesystem resize +10G /mnt/tmp1
 Resize '/mnt/tmp1' of '+10G'
 ERROR: unable to resize '/mnt/tmp1' - no enouth free space
 #

Reported-by: Taeha Kim <kthguru@gmail.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>