Build userland examples separately

packages/kernel_modules/userland/rdtsc.c

@@ -0,0 +1,20 @@
+/* https://github.com/cirosantilli/linux-kernel-module-cheat#rdtsc */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#if defined(__i386__) || defined(__x86_64__)
+#include <x86intrin.h>
+#endif
+
+int main(void) {
+	uintmax_t val;
+#if defined(__i386__) || defined(__x86_64__)
+	val = __rdtsc();
+#else
+	val = 0;
+#endif
+	printf("%ju\n", val);
+	return EXIT_SUCCESS;
+}