acpi: remerge uacpi as inhouse

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

libs/uacpi/uacpi.cmake

@@ -0,0 +1,34 @@
+# This cmake file is not meant to be used to actually build the project.
+# Instead, it is supposed to be included via 'include()' by the actual
+# CMakeLists.txt file, which intends to use uACPI. This file takes care of
+# accumulating all sources & includes into well-defined exported variables
+# that the parent cmake file is supposed to make use of.
+
+# ======== Exported public variables =========
+
+# A list that contains all of the compilable files that must be compiled along
+# with all other source files (added via target_sources etc).
+set(UACPI_SOURCES "")
+
+# A list that contains all of the include paths that must be appended to the
+# parent include directories (via target_include_directories etc).
+set(UACPI_INCLUDES "")
+
+# absolute path to the uACPI root directory
+set(UACPI_ROOT_DIR "${CMAKE_CURRENT_LIST_DIR}")
+
+# ============================================
+
+list(APPEND UACPI_INCLUDES "${UACPI_ROOT_DIR}/include")
+
+macro(uacpi_add_sources)
+    foreach (SOURCE_FILE ${ARGV})
+        list(APPEND UACPI_SOURCES "${CMAKE_CURRENT_LIST_DIR}/${SOURCE_FILE}")
+    endforeach()
+endmacro()
+
+macro(uacpi_subdir SUBDIR)
+    include("${UACPI_ROOT_DIR}/${SUBDIR}/files.cmake")
+endmacro()
+
+uacpi_subdir(source)