Implement async termination of blocking thread (#2516)

Send a signal whose handler is no-op to a blocking thread to wake up
the blocking syscall with either EINTR equivalent or partial success.

Unlike the approach taken in the `dev/interrupt_block_insn` branch (that is,
signal + longjmp similarly to `OS_ENABLE_HW_BOUND_CHECK`), this PR
does not use longjmp because:
* longjmp from signal handler doesn't work on nuttx
  refer to https://github.com/apache/nuttx/issues/10326
* the singal+longjmp approach may be too difficult for average programmers
  who might implement host functions to deal with

See also https://github.com/bytecodealliance/wasm-micro-runtime/issues/1910

core/shared/platform/include/platform_api_extension.h

@@ -323,6 +323,34 @@ os_sem_getvalue(korp_sem *sem, int *sval);
 int
 os_sem_unlink(const char *name);
 
+/**
+ * Initialize process-global state for os_wakeup_blocking_op.
+ */
+int
+os_blocking_op_init();
+
+/**
+ * Start accepting os_wakeup_blocking_op requests for the calling thread.
+ */
+void
+os_begin_blocking_op();
+
+/**
+ * Stop accepting os_wakeup_blocking_op requests for the calling thread.
+ */
+void
+os_end_blocking_op();
+
+/**
+ * Wake up the specified thread.
+ *
+ * For example, on posix-like platforms, this can be implemented by
+ * sending a signal (w/o SA_RESTART) which interrupts a blocking
+ * system call.
+ */
+int
+os_wakeup_blocking_op(korp_tid tid);
+
 /****************************************************
  *                     Section 2                    *
  *                   Socket support                 *