kernel-doc: core-api: include string.h into core-api [joe@perches.com: correct return of -E2BIG descriptions] ...beae70500ba0daa4b340c546.1563889130.git.joe@perches.com ...07c0c376d66155d970e46733.1563841972.git.joe@perches.com Signed-off-by: Joe Perches <joe@perches.com>