ocfs2: Fix 2 warning during ocfs2 make.

fs/ocfs2/dir.c: In function ‘ocfs2_extend_dir’:
fs/ocfs2/dir.c:2700: warning: ‘ret’ may be used uninitialized in this function

fs/ocfs2/suballoc.c: In function ‘ocfs2_get_suballoc_slot_bit’:
fs/ocfs2/suballoc.c:2216: warning: comparison is always true due to limited range of data type

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>