Btrfs-progs: fix compile warnings in i386 machine

Btrfs-progs: fix compile warnings in i386 machine

See the warnings below:

   [CC]     btrfs-list.o
btrfs-list.c: In function 'filter_by_parent':
btrfs-list.c:1183:34: warning: cast to pointer from integer of different size
[-Wint-to-pointer-cast]
     [CC]     cmds-subvolume.o
cmds-subvolume.c: In function 'cmd_subvol_show':
cmds-subvolume.c:917:5: warning: cast from pointer to integer of different size
[-Wpointer-to-int-cast]
     [CC]     cmds-restore.o
cmds-restore.c: In function 'decompress_lzo':
cmds-restore.c:116:10: warning: passing argument 4 of 'lzo1x_decompress_safe'
from incompatible pointer type [enabled by default]
In file included from cmds-restore.c:31:0:
/usr/include/lzo/lzo1x.h:77:1: note: expected 'lzo_uint *' but argument is of
type 'size_t *'

Reported-by: Russell Coker <russell@coker.com.au>
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>