devres: Add devm_kasprintf and devm_kvasprintf API

devres: Add devm_kasprintf and devm_kvasprintf API

devm_kasprintf() and devm_kvasprintf() are the managed counterparts
for kasprintf() and kvasprintf().

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 75f2a4ead5d5890ada9c2663a70fb58613c0d9f2)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Conflicts:
	drivers/base/devres.c