gpio: ts4800: Remove duplicate code to handle 'ngpios' property

gpio: ts4800: Remove duplicate code to handle 'ngpios' property

The gpio_generic_chip_init() handles the 'ngpios' property and
assigns the respective field in struct gpio_chip either with
the value of it, or, if not found, with the default based on
the register size. There is no need to repeat this in the driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Link: https://patch.msgid.link/20260219134647.2258593-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>