watchdog: sp805_wdt: add arm cmsdk apb wdt support

watchdog: sp805_wdt: add arm cmsdk apb wdt support

Support arm CMSDK ip apb watchdog device.
Description details of this device can be found in the
document DDI0479D_m_class_processor_system_r1p1_trm.pdf
on the arm's document web. Which periphid is 0x001bb824.
The registers are basically the same as the 805, just a
few more: Periphid4/5/6/7 with offset 0xFD0/0xFD4/0xFD8/0xFDC.
For the register description of arm,sp805, please refer
to the document DDI0270-arm-sp805.pdf.

Signed-off-by: Bing Fan <tombinfan@tencent.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/1656037482-19505-1-git-send-email-hptsfb@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>