Move generic start code and memset into arch/generic.h

arch/generic.h

@@ -0,0 +1,31 @@
+/*
+ * This file is not meant to be included by user applications
+ * It contains generic arch agnostic implementations of helper functions
+ * and start code that can be included in <arch>.c when an architecture
+ * specific version is not nessisary.
+ *
+ * Copyright (c) 2025 Lucas Schumacher. All Rights Reserved.
+ */
+
+#ifndef MEMSET_DEFINED
+#define MEMSET_DEFINED
+// Generic memset implementation
+void *memset(void* s, int c, unsigned long n) {
+  int8_t* mem = s;
+  for(long int i = 0; i < n; ++i) mem[i] = c;
+  return s;
+}
+#endif // !MEMSET_DEFINED
+
+#ifndef _START_DEFINED
+#define _START_DEFINED
+// Generic _start implementation. Can't access any args
+extern void exit(int8_t status);
+extern int main(int argc, char** argv);
+void _start() {
+  exit(main(0, 0));
+}
+void __start() {
+  exit(main(0, 0));
+}
+#endif // !_START_DEFINED