gpio: sch: depends on LPC_SCH

Since LPC_SCH provides GPIO functionality, GPIO_SCH should depend on
LPC_SCH to prevent kconfig warning and build errors:

WARNING: unmet direct dependencies detected for LPC_SCH
  Depends on [n]: HAS_IOMEM [=y] && PCI [=n]
  Selected by [y]:
  - GPIO_SCH [=y] && GPIOLIB [=y] && X86 [=y] && (X86 [=y] || COMPILE_TEST [=n]) && ACPI [=y]

and

../drivers/mfd/lpc_sch.c:204:1: warning: data definition has no type or storage class
 module_pci_driver(lpc_sch_driver);
 ^~~~~~~~~~~~~~~~~
../drivers/mfd/lpc_sch.c:204:1: error: type defaults to ‘int’ in declaration of ‘module_pci_driver’ [-Werror=implicit-int]
../drivers/mfd/lpc_sch.c:204:1: warning: parameter names (without types) in function declaration
../drivers/mfd/lpc_sch.c:197:26: warning: ‘lpc_sch_driver’ defined but not used [-Wunused-variable]
 static struct pci_driver lpc_sch_driver = {
                          ^~~~~~~~~~~~~~

Fixes: 6c46215d6b62 ("gpio: sch: Hook into ACPI GPE handler to catch GPIO edge events")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-gpio@vger.kernel.org
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Denis Turischev <denis@compulab.co.il>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>