arm: support restart through restart handler call chain
arm: support restart through restart handler call chain

The kernel core now supports a restart handler call chain for system
restart functions.

With this change, the arm_pm_restart callback is now optional, so drop its
initialization and check if it is set before calling it.  Only call the
kernel restart handler if arm_pm_restart is not set.

Signed-off-by: Guenter Roeck <ba324ca7b1c77fc20bb970d5aff6eea9377918a5@roeck-us.net>
Acked-by: Catalin Marinas <15ce75b290ebaf27c3f9fd73ab848685ed3d8261@arm.com>
Acked-by: Heiko Stuebner <9ab5f52a1ca0bcf4f70d6d9008e02f6134b5b8f2@sntech.de>
Cc: Arnd Bergmann <f2c659f01951776204a6c5b902787d9019fbeebd@arndb.de>
Cc: David Woodhouse <97b3379caa91f4ee97e44013ae4dc6350540fa9d@infradead.org>
Cc: Dmitry Eremin-Solenikov <b6edad08270b2e4ffbcb0879e25a0e29a48c5275@gmail.com>
Cc: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@kernel.org>
Cc: Jonas Jensen <c72f4c1d52c160086195ed01f658663cef237767@gmail.com>
Cc: Maxime Ripard <2d324f4ca95610bde432fa2af2f28cd21110687d@free-electrons.com>
Cc: Randy Dunlap <6f29df8e90a57f1ba61ffd63b0468c86bb6d3a99@infradead.org>
Cc: Russell King <ba324ca7b1c77fc20bb970d5aff6eea9377918a5@arm.linux.org.uk>
Cc: Steven Rostedt <43232e92d70cc7aa53504ad0397085ee47bad87f@goodmis.org>
Cc: Tomasz Figa <c4885e520559c7b5b4fe1e9e188b924d2debd35e@samsung.com>
Cc: Will Deacon <b913f13ef92ac157955c954ccaaff7be065faba4@arm.com>
Cc: Wim Van Sebroeck <5f65f6985de1ebf15dde04e0dc4668211868bafa@iguana.be>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs