libgpiod: remove dependency to kernel version

Now that we only use kernel versions that support libgpiod,
we can remove the dependency on the kernel version.

This enables libgpiod to be used with linux 4.19.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>

libs/libgpiod/Makefile

@@ -34,7 +34,7 @@ define Package/libgpiod
   CATEGORY:=Libraries
   URL:=https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git
   TITLE:=Library for interacting with Linux's GPIO character device
-  DEPENDS:=@GPIO_SUPPORT @(LINUX_4_9||LINUX_4_14)
+  DEPENDS:=@GPIO_SUPPORT
 endef
 
 define Package/libgpiod/description