kernel.h/checkpatch: mark strict_strto<foo> and simple_strto<foo> as obsolete

Mark obsolete/deprecated strict_strto<foo> and simple_strto<foo> functions
and macros as obsolete.

Update checkpatch to warn about their use.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>