arm64: defconfig: Enable BCM2712 on-chip pin controller driver

Select the on-chip pin controller driver for BCM2712 SoC.

On RapsberryPi 5 devices it is primarily needed to operate the
bluetooth and WiFi devices, to configure the uSD interface
and the power button.

Signed-off-by: Andrea della Porta <andrea.porta@suse.com>
Link: https://lore.kernel.org/all/38704a5ab6913845bbf9178170e83004ab3e8fcf.1756372805.git.andrea.porta@suse.com/


Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>