readme: more info on kernel panics, oops an backtraces.

myinsmod: use either finit or init

kernel_module/dump_stack.c

@@ -0,0 +1,19 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+
+static int myinit(void)
+{
+	pr_info("dump_stack myinit\n");
+	dump_stack();
+	pr_info("dump_stack after\n");
+	return 0;
+}
+
+static void myexit(void)
+{
+	pr_info("panic myexit\n");
+}
+
+module_init(myinit)
+module_exit(myexit)
+MODULE_LICENSE("GPL");