ANDROID: Incremental fs: Fix misuse of cpu_to_leXX and poll return

Found by sparse:

fs/incfs/format.c:416:21: warning: incorrect type in assignment (different base types)
fs/incfs/format.c:416:21:    expected restricted __le32 [assigned] [usertype] fh_flags
fs/incfs/format.c:416:21:    got int

fs/incfs/pseudo_files.c:925:25: warning: incorrect type in argument 4 (different base types)
fs/incfs/pseudo_files.c:925:25:    expected unsigned long long [usertype] size
fs/incfs/pseudo_files.c:925:25:    got restricted __le64 [addressable] [assigned] [usertype] size_attr_value
fs/incfs/pseudo_files.c:925:42: warning: incorrect type in argument 5 (different base types)
fs/incfs/pseudo_files.c:925:42:    expected unsigned long long [usertype] offset
fs/incfs/pseudo_files.c:925:42:    got restricted __le64 [usertype]
fs/incfs/pseudo_files.c:1111:24: warning: incorrect type in return expression (different base types)
fs/incfs/pseudo_files.c:1111:24:    expected restricted __poll_t
fs/incfs/pseudo_files.c:1111:24:    got int

Bug: 169258814
Fixes: Sparse errors introduced by 3f4938108a7ad, 8334d69e65f60 and cb776f45766a6
Test: incfs_test passes, sparse shows no errors
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Change-Id: I509b113cec0c769df4824abcf5154b9936608038