Update libsrtp to 1.5.2

srtp/crypto/test/datatypes_driver.c

 /*
  * datatypes_driver.c
  *
  * a test driver for crypto/math datatypes
  *
  * David A. McGrew
  * Cisco Systems, Inc.
  */
 
 /*
@@ skipping 191 matching lines @@
 
   len = hex_string_to_octet_string(raw, hex2, strlen(hex2));
   printf("computed length: %d\tstring: %s\n", len,
          octet_string_hex_string(raw, len/2));
   printf("expected length: %d\tstring: %s\n", 16, "0123456789abcdef");
 
 }
 
 void
 print_string(char *s) {
-  int i;  
+  size_t i;
   printf("%s\n", s);
   printf("strlen(s) = %u\n", (unsigned)strlen(s));
   printf("{ ");
   for (i=0; i < strlen(s); i++) {
     printf("0x%x, ", s[i]);
     if (((i+1) % 8) == 0)
       printf("\n   ");
   }
   printf("}\n");
 }
 
 void
 test_bswap(void) {
   uint32_t x = 0x11223344;
   uint64_t y = 0x1122334455667788LL;
 
   printf("before: %0x\nafter:  %0x\n", x, be32_to_cpu(x));
   printf("before: %0llx\nafter:  %0llx\n", (unsigned long long)y,
          (unsigned long long)be64_to_cpu(y));
 
   y = 1234;
 
   printf("1234: %0llx\n", (unsigned long long)y);
   printf("as octet string: %s\n", 
          octet_string_hex_string((uint8_t *) &y, 8));
   y = be64_to_cpu(y);
   printf("bswapped octet string: %s\n", 
          octet_string_hex_string((uint8_t *) &y, 8));
 }