Use os_memdup()

This leads to cleaner code overall, and also reduces the size
of the hostapd and wpa_supplicant binaries (in hwsim test build
on x86_64) by about 2.5 and 3.5KiB respectively.

The mechanical conversions all over the code were done with
the following spatch:

    @@
    expression SIZE, SRC;
    expression a;
    @@
    -a = os_malloc(SIZE);
    +a = os_memdup(SRC, SIZE);
    <...
    if (!a) {...}
    ...>
    -os_memcpy(a, SRC, SIZE);

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

src/crypto/aes-siv.c

@@ -95,11 +95,10 @@ static int aes_s2v(const u8 *key, size_t key_len,
 		xor(tmp, tmp2);
 	}
 	if (len[i] >= AES_BLOCK_SIZE) {
-		buf = os_malloc(len[i]);
+		buf = os_memdup(addr[i], len[i]);
 		if (!buf)
 			return -ENOMEM;
 
-		os_memcpy(buf, addr[i], len[i]);
 		xorend(buf, len[i], tmp, AES_BLOCK_SIZE);
 		data[0] = buf;
 		ret = omac1_aes_vector(key, key_len, 1, data, &len[i], mac);