test_firmware: Use kstrtobool() instead of strtobool()

stable inclusion
from stable-v5.10.185
commit 682ca602515ddec705451a738f8e7310fed3dc77
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8J4KH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=682ca602515ddec705451a738f8e7310fed3dc77



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[ Upstream commit f7d85515 ]

strtobool() is the same as kstrtobool().
However, the latter is more used within the kernel.

In order to remove strtobool() and slightly simplify kstrtox.h, switch to
the other function name.

While at it, include the corresponding header file (<linux/kstrtox.h>)

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/34f04735d20e0138695dd4070651bd860a36b81c.1673688120.git.christophe.jaillet@wanadoo.fr


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 4acfe3df ("test_firmware: prevent race conditions by a correct implementation of locking")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>