fix haiku

core/sys/posix/time.odin

@@ -1,4 +1,4 @@
-#+build linux, darwin, netbsd, openbsd, freebsd
+#+build linux, darwin, netbsd, openbsd, freebsd, haiku
 package posix
 
 import "core:c"
@@ -230,6 +230,17 @@ when ODIN_OS == .Darwin {
 
 	getdate_err: Errno = .ENOSYS // NOTE: looks like it's not a thing on OpenBSD.
 
+} else when ODIN_OS == .Haiku {
+
+	clockid_t :: distinct c.int32_t
+
+	CLOCK_MONOTONIC          :: 0
+	CLOCK_PROCESS_CPUTIME_ID :: -2
+	CLOCK_REALTIME           :: -1
+	CLOCK_THREAD_CPUTIME_ID  :: -3
+
+	getdate_err: Errno = .ENOSYS // NOTE: looks like it's not a thing on Haiku.
+
 } else when ODIN_OS == .Linux {
 
 	clockid_t :: distinct c.int