compiler: Merge the runtime into the Go code, for better code size

src/runtime/runtime.c

@@ -1,15 +1,19 @@
 
 #include "runtime.h"
+#include <string.h>
 
 void go_main() __asm__("main.main");
 
-void __go_runtime_main() {
-	go_main();
-}
-
-__attribute__((weak))
 int main() {
-	__go_runtime_main();
+	go_main();
 
 	return 0;
 }
+
+__attribute__((weak))
+void * memset(void *s, int c, size_t n) {
+	for (size_t i = 0; i < n; i++) {
+		((uint8_t*)s)[i] = c;
+	}
+	return s;
+}

src/runtime/runtime_nrf.c

@@ -2,6 +2,7 @@
 #include "hal/nrf_uart.h"
 #include "nrf.h"
 #include "runtime.h"
+#include <string.h>
 
 void uart_init(uint32_t pin_tx) {
 	NRF_UART0->ENABLE        = UART_ENABLE_ENABLE_Enabled;
@@ -30,9 +31,7 @@ __attribute__((weak))
 void __aeabi_memclr(uint8_t *dest, size_t n) {
 	// TODO: link with compiler-rt for a better implementation.
 	// For now, use a simple memory zeroer.
-	for (size_t i = 0; i < n; i++) {
-		dest[i] = 0;
-	}
+	memset(dest, 0, n);
 }
 
 __attribute__((weak))