[PATCH 2/2] atomic_ops.rst: Use `warning` rst directive

[SeongJae Park]

One warning message in 'atomic_ops.rst' is not using 'warning' rst
directive while others does.  This commit modifies the message to use
'warning' rst directive.

Signed-off-by: SeongJae Park <sj38.park@xxxxxxxxx>
---
 Documentation/core-api/atomic_ops.rst | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/Documentation/core-api/atomic_ops.rst b/Documentation/core-api/atomic_ops.rst
index 4ea4af71e68a..2e7165f86f55 100644
--- a/Documentation/core-api/atomic_ops.rst
+++ b/Documentation/core-api/atomic_ops.rst
@@ -466,10 +466,12 @@ Like the above, except that these routines return a boolean which
 indicates whether the changed bit was set _BEFORE_ the atomic bit
 operation.
 
-WARNING! It is incredibly important that the value be a boolean,
-ie. "0" or "1".  Do not try to be fancy and save a few instructions by
-declaring the above to return "long" and just returning something like
-"old_val & mask" because that will not work.
+
+.. warning::
+        It is incredibly important that the value be a boolean, ie. "0" or "1".
+        Do not try to be fancy and save a few instructions by declaring the
+        above to return "long" and just returning something like "old_val &
+        mask" because that will not work.
 
 For one thing, this return value gets truncated to int in many code
 paths using these interfaces, so on 64-bit if the bit is set in the
-- 
2.13.0