mfd: vexpress-sysreg: Check the return value of devm_gpiochip_add_data()

mfd: vexpress-sysreg: Check the return value of devm_gpiochip_add_data()

Commit 974cc7b93441 ("mfd: vexpress: Define the device as MFD cells")
removed the return value check from the call to gpiochip_add_data() (or
rather gpiochip_add() back then and later converted to devres) with no
explanation. This function however can still fail, so check the return
value and bail-out if it does.

Cc: stable@vger.kernel.org
Fixes: 974cc7b93441 ("mfd: vexpress: Define the device as MFD cells")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250811-gpio-mmio-mfd-conv-v1-1-68c5c958cf80@linaro.org
Signed-off-by: Lee Jones <lee@kernel.org>