Actually include sys/endian.h for le32enc/le32dec

While here, fix a typo

src/scrypt.h

@@ -2,6 +2,9 @@
 #define SCRYPT_H
 #include <stdlib.h>
 #include <stdint.h>
+#ifdef __FreeBSD__
+# include <sys/endian.h>
+#endif
 static const int SCRYPT_SCRATCHPAD_SIZE = 131072 + 63;
 
 void scrypt_1024_1_1_256(const char *input, char *output);
@@ -18,7 +21,7 @@ PBKDF2_SHA256(const uint8_t *passwd, size_t passwdlen, const uint8_t *salt,
     size_t saltlen, uint64_t c, uint8_t *buf, size_t dkLen);
 
 # ifndef __FreeBSD__
-/* Allready defined in sys/endian.h */
+/* Already defined in sys/endian.h */
 static inline uint32_t le32dec(const void *pp)
 {
         const uint8_t *p = (uint8_t const *)pp;