Fix spelling and typographical errors found by cspell

Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/include/mbedtls/camellia.h b/include/mbedtls/camellia.h
index 925a623..d39d932 100644
--- a/include/mbedtls/camellia.h
+++ b/include/mbedtls/camellia.h
@@ -273,7 +273,7 @@
  *             encrypted: for example, with 96-bit random nonces, you should
  *             not encrypt more than 2**32 messages with the same key.
  *
- *             Note that for both stategies, sizes are measured in blocks and
+ *             Note that for both strategies, sizes are measured in blocks and
  *             that a CAMELLIA block is \c 16 Bytes.
  *
  * \warning    Upon return, \p stream_block contains sensitive data. Its