fix formatting for bulleted list (KhronosGroup#1253)

Author: bashbaug

api/opencl_runtime_layer.asciidoc

@@ -5438,7 +5438,8 @@ acquired.
 This is to guarantee that the state of the memory objects is up-to-date and
 they are accessible to OpenCL.
 
-The following restrictions shall apply -
+The following restrictions shall apply:
+
   * Each memory object must be acquired only once. Acquiring a memory object 
     multiple times without releasing it results in implementation-defined
     behavior.
@@ -5531,7 +5532,8 @@ commands in the other API.
 This is to guarantee that the state of memory objects is up-to-date and they
 are accessible to the other API.
 
-The following restrictions shall apply -
+The following restrictions shall apply:
+
   * Each memory object must be released only once. Releasing a memory object 
     multiple times without acquiring it results in implementation-defined
     behavior.