Weaken more init/env functions (#451)

libctru/source/env.c

@@ -37,7 +37,7 @@ static int __name_cmp(const char* a, const char* b) {
 	return 0;
 }
 
-Handle envGetHandle(const char* name) {
+Handle __attribute__((weak)) envGetHandle(const char* name) {
 	if(__service_ptr == NULL)
 		return 0;
 
@@ -52,7 +52,7 @@ Handle envGetHandle(const char* name) {
 	return 0;
 }
 
-void envDestroyHandles(void) {
+void __attribute__((weak)) envDestroyHandles(void) {
 	if(__service_ptr == NULL)
 		return;
 

libctru/source/system/initArgv.c

@@ -10,7 +10,7 @@ char** __system_argv;
 extern char* fake_heap_start;
 extern char* fake_heap_end;
 
-void __system_initArgv(void)
+void __attribute__((weak)) __system_initArgv(void)
 {
 	int i;
 	const char* arglist = envGetSystemArgList();

libctru/source/system/syscalls.c

@@ -35,7 +35,7 @@ static int __libctru_nanosleep(const struct timespec *req, struct timespec *rem)
 }
 
 
-void __system_initSyscalls(void)
+void __attribute__((weak)) __system_initSyscalls(void)
 {
 	// Register newlib syscalls
 	__syscalls.exit     = __ctru_exit;