[PATCH] docs: arm64: Fix indentation and doc formatting

[Adam Zerella <adam.zerella@gmail.com>]

Sphinx generates the following warnings for the arm64 doc
pages:

Documentation/arm64/memory.rst:158: WARNING: Unexpected indentation.
Documentation/arm64/memory.rst:162: WARNING: Unexpected indentation.

These indentations warnings can be resolved by utilising code
hightlighting instead.

Signed-off-by: Adam Zerella <adam.zerella@gmail.com>
---
 Documentation/arm64/memory.rst | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/Documentation/arm64/memory.rst b/Documentation/arm64/memory.rst
index b040909e45f8..f7db6a3898c5 100644
--- a/Documentation/arm64/memory.rst
+++ b/Documentation/arm64/memory.rst
@@ -154,11 +154,16 @@ return virtual addresses to userspace from a 48-bit range.
 
 Software can "opt-in" to receiving VAs from a 52-bit space by
 specifying an mmap hint parameter that is larger than 48-bit.
-For example:
-    maybe_high_address = mmap(~0UL, size, prot, flags,...);
+
+.. code-block:: c
+
+   maybe_high_address = mmap(~0UL, size, prot, flags,...);
 
 It is also possible to build a debug kernel that returns addresses
 from a 52-bit space by enabling the following kernel config options:
+
+.. code-block:: sh
+
    CONFIG_EXPERT=y && CONFIG_ARM64_FORCE_52BIT=y
 
 Note that this option is only intended for debugging applications
-- 
2.20.1