ARM: decompress: remove unused ARCH_HAS_DECOMP_WDOG

ARCH_HAS_DECOMP_WDOG is only used in lib/inflate.c which is not
included in arch/arm/boot/compressed/decompress.c now.  That said,
ARCH_HAS_DECOMP_WDOG is not used at all.  Let's remove it.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>

arch/arm/boot/compressed/decompress.c

@@ -13,8 +13,6 @@ extern void error(char *);
 #define STATIC static
 #define STATIC_RW_DATA	/* non-static please */
 
-#define ARCH_HAS_DECOMP_WDOG
-
 /* Diagnostic functions */
 #ifdef DEBUG
 #  define Assert(cond,msg) {if(!(cond)) error(msg);}