Docs: Rename duplicate title in porting guide
Fix one of the two titles that ended up being the same, although both
describe different things.
Change-Id: I66ecf369643709898ee4c014659d8f85c0480643
diff --git a/docs/porting-guide.md b/docs/porting-guide.md
index 93c0169..8e913b9 100644
--- a/docs/porting-guide.md
+++ b/docs/porting-guide.md
@@ -8,7 +8,7 @@
2. [Common Modifications](#2--common-modifications)
* [Common mandatory modifications](#21-common-mandatory-modifications)
* [Handling reset](#22-handling-reset)
- * [Common mandatory modifications](#23-common-mandatory-modifications)
+ * [Common mandatory function modifications](#23-common-mandatory-function-modifications)
* [Common optional modifications](#24-common-optional-modifications)
3. [Boot Loader stage specific modifications](#3--modifications-specific-to-a-boot-loader-stage)
* [Boot Loader stage 1 (BL1)](#31-boot-loader-stage-1-bl1)
@@ -685,7 +685,7 @@
not be updated.
-2.3 Common mandatory modifications
+2.3 Common mandatory function modifications
---------------------------------
The following functions are mandatory functions which need to be implemented