Update OCL synopsis to match description

Add the `blocking_read` / `blocking_write` parameters also to the
synopsis listing.

Author: gmlueck

sycl/doc/extensions/DeviceGlobal/cl_intel_global_variable_access.asciidoc

@@ -68,6 +68,7 @@ cl_int clEnqueueReadGlobalVariableINTEL(
     cl_command_queue command_queue,
     cl_program program,
     const char* name,
+    cl_bool blocking_read,
     size_t size,
     size_t offset,
     void* ptr,
@@ -79,6 +80,7 @@ cl_int clEnqueueWriteGlobalVariableINTEL(
     cl_command_queue command_queue,
     cl_program program,
     const char* name,
+    cl_bool blocking_write,
     size_t size,
     size_t offset,
     const void* ptr,