refactor: Disallow multiple initialised declarators per decl.

We no longer allow:

```c
int a = 0, b = 0;
int a[3], b[3];
int a, *b;
```

But we do still allow (for now):

```c
int a, b;
```

1 files changed, 2 insertions, 1 deletions

diff --git a/toxcore/Messenger.c b/toxcore/Messenger.c
index 32c89867..573cd64a 100644
--- a/toxcore/Messenger.c
+++ b/toxcore/Messenger.c
@@ -239,7 +239,8 @@ int32_t m_addfriend(Messenger *m, const uint8_t *address, const uint8_t *data, u
         return FAERR_BADCHECKSUM;
     }
 
-    uint16_t check, checksum = address_checksum(address, FRIEND_ADDRESS_SIZE - sizeof(checksum));
+    uint16_t check;
+    uint16_t checksum = address_checksum(address, FRIEND_ADDRESS_SIZE - sizeof(checksum));
     memcpy(&check, address + CRYPTO_PUBLIC_KEY_SIZE + sizeof(uint32_t), sizeof(check));
 
     if (check != checksum) {