build submodule: added cmake subdirectory config

Signed-off-by: John Sanpe <sanpeqf@gmail.com>

Author: pixclk

bfdev.cmake

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Copyright(c) 2025 John Sanpe <sanpeqf@gmail.com>
+#
+
+set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
+add_subdirectory(${CMAKE_CURRENT_LIST_DIR})
+
+get_property(BFDEV_INCLUDE_DIRS GLOBAL PROPERTY "BFDEV_INCLUDE_DIRS")
+include_directories(${BFDEV_INCLUDE_DIRS})