Add FindLibUSB.cmake for libftdi

cmake/FindLibUSB.cmake

@@ -0,0 +1,17 @@
+find_package(PkgConfig)
+pkg_check_modules(LibUSB QUIET libusb)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(LibUSB
+    REQUIRED_VARS
+        LibUSB_INCLUDE_DIRS
+        LibUSB_LIBRARIES
+)
+
+if(LibUSB_FOUND AND NOT TARGET LibUSB::LibUSB)
+    add_library(LibUSB::LibUSB INTERFACE IMPORTED)
+    set_target_properties(LibUSB::LibUSB PROPERTIES
+        INTERFACE_INCLUDE_DIRECTORIES "${LibUSB_INCLUDE_DIRS}"
+        INTERFACE_LINK_LIBRARIES "${LibUSB_LIBRARIES}"
+    )
+endif()