[os2]: Implement pipe_has_data procedure

core/sys/windows/kernel32.odin

@@ -381,6 +381,14 @@ foreign kernel32 {
 		nDefaultTimeOut: DWORD,
 		lpSecurityAttributes: LPSECURITY_ATTRIBUTES,
 	) -> HANDLE ---
+	PeekNamedPipe :: proc(
+        hNamedPipe: HANDLE,
+        lpBuffer: rawptr,
+        nBufferSize: u32,
+        lpBytesRead: ^u32,
+        lpTotalBytesAvail: ^u32,
+        lpBytesLeftThisMessage: ^u32,
+    ) -> BOOL ---
 	CancelIo :: proc(handle: HANDLE) -> BOOL ---
 	GetOverlappedResult :: proc(
 		hFile: HANDLE,