Fix typographical errors in .md files found by cspell

Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/docs/architecture/psa-crypto-implementation-structure.md b/docs/architecture/psa-crypto-implementation-structure.md
index cd4d427..6a0a095 100644
--- a/docs/architecture/psa-crypto-implementation-structure.md
+++ b/docs/architecture/psa-crypto-implementation-structure.md
@@ -1,4 +1,4 @@
-PSA Cryptograpy API implementation and PSA driver interface
+PSA Cryptography API implementation and PSA driver interface
 ===========================================================
 
 ## Introduction