gpio: f7188x: set can_sleep attribute

Since request_muxed_region() is used to synchronize access on the
Super-I/O controller, then the can_sleep attribute must be set for
the f7188x GPIO chips.

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-f7188x.c b/drivers/gpio/gpio-f7188x.c
index 9cb8320..8f73ee0 100644
--- a/drivers/gpio/gpio-f7188x.c
+++ b/drivers/gpio/gpio-f7188x.c
@@ -135,6 +135,7 @@
 			.set              = f7188x_gpio_set,		\
 			.base             = _base,			\
 			.ngpio            = _ngpio,			\
+			.can_sleep        = true,			\
 		},							\
 		.regbase = _regbase,					\
 	}