Fix spelling and typographical errors found by cspell

Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/include/mbedtls/blowfish.h b/include/mbedtls/blowfish.h
index 15a49c5..d5f8099 100644
--- a/include/mbedtls/blowfish.h
+++ b/include/mbedtls/blowfish.h
@@ -246,7 +246,7 @@
  *             The recommended way to ensure uniqueness is to use a message
  *             counter.
  *
- *             Note that for both stategies, sizes are measured in blocks and
+ *             Note that for both strategies, sizes are measured in blocks and
  *             that a Blowfish block is 8 bytes.
  *
  * \warning    Upon return, \p stream_block contains sensitive data. Its