get rid of lkmc package, move userland and kernel-modules to top

Rationale: we already had a non buildroot build system,
maintaining both will be hard, and having short paths is more awesome.

userland/hello.c

@@ -0,0 +1,9 @@
+/* https://github.com/cirosantilli/linux-kernel-module-cheat#sanity-checks */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void) {
+	puts("hello");
+	return EXIT_SUCCESS;
+}