Fix typos and misspellings

Fix a number of typos and misspellings in TF-A
documentation and comments.

Signed-off-by: David Horstmann <david.horstmann@arm.com>
Change-Id: I34c5a28c3af15f28d1ccada4d9866aee6af136ee
diff --git a/docs/getting_started/porting-guide.rst b/docs/getting_started/porting-guide.rst
index 19e26e4..d063ec7 100644
--- a/docs/getting_started/porting-guide.rst
+++ b/docs/getting_started/porting-guide.rst
@@ -116,7 +116,7 @@
    by ``plat/common/aarch64/platform_mp_stack.S`` and
    ``plat/common/aarch64/platform_up_stack.S``.
 
--  **define : CACHE_WRITEBACK_GRANULE**
+-  **#define : CACHE_WRITEBACK_GRANULE**
 
    Defines the size in bits of the largest cache line across all the cache
    levels in the platform.