modify the return value according to posix standard
------------
SCHED_GET_PRIORITY_MAX(2)
NAME
sched_get_priority_max, sched_get_priority_min - get static priority range
RETURN VALUE
On success, sched_get_priority_max() and sched_get_priority_min() return the
maximum/minimum priority value for the named scheduling policy.
On error, -1 is returned, and errno is set appropriately.
ERRORS
EINVAL The argument policy does not identify a defined scheduling policy.
Signed-off-by: chao an <anchao@xiaomi.com>
Squashed commit of the following:
libs/libxx: Fix some confusing in naming. If the directory is called libxx, then the library must be libxx.a (unless perhaps LIBCXX is selected).
libs/: Fix paths in moved library directories.
libs: Brute force move of libc, libnx, and libxx to libs. Cannot yet build it in that configuration.
