fs/binfmt_elf.c: delete trailing "return;" in functions returning "void"

Link: http://lkml.kernel.org/r/20190314205042.GE18143@avx2


Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>