riscv: dts: spacemit: pinctrl: update register and IO power

riscv: dts: spacemit: pinctrl: update register and IO power

Change the size of the reg register to 0x1000 to match the hardware.
This register range covers the IO power domain's register addresses.

The IO power domain registers are protected. In order to access the
protected IO power domain registers, a valid unlock sequence must be
performed by writing the required keys to the AIB Secure Access Register
(ASAR).

The ASAR register resides within the APBC register address space.
A corresponding syscon property `spacemit,apbc` is added to allow
the pinctrl driver to access this register.

Signed-off-by: Troy Mitchell <troy.mitchell@linux.spacemit.com>
Acked-by: Linus Walleij <linusw@kernel.org>
Link: https://lore.kernel.org/r/20260108-kx-pinctrl-aib-io-pwr-domain-v2-3-6bcb46146e53@linux.spacemit.com
Signed-off-by: Yixun Lan <dlan@kernel.org>