util: Rename DETECT_OS_UNIX to DETECT_OS_POSIX
What does this MR do and why?
Rationale: !29539 (comment 2439170)
cc @robclark
util: Rename DETECT_OS_UNIX to DETECT_OS_POSIX
Looking at each usage of DETECT_OS_UNIX, it's more about the POSIX API usage, not the
Unix-like OS, so let's rename it
And for POSIX it's a standard to claim which API present, but for UNIX there is no such thing
Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Edited by Yonggang Luo