vfs: add vfs_cdcacm driver (aka USB CDC)

components/vfs/CMakeLists.txt

@@ -3,6 +3,10 @@ idf_component_register(SRCS "vfs.c"
                             "vfs_semihost.c"
                     INCLUDE_DIRS include)
 
+if(CONFIG_ESP_CONSOLE_USB_CDC)
+    target_sources(${COMPONENT_LIB} PRIVATE "vfs_cdcacm.c")
+endif()
+
 # Some newlib syscalls are implemented in vfs.c, make sure these are always
 # seen by the linker
 target_link_libraries(${COMPONENT_LIB} INTERFACE "-u vfs_include_syscalls_impl")