sh: Add the old invalidate_icache_all function

Add the old invalidate_icache_all function that prints a warning that
was previously found in cmd/cache.c

Signed-off-by: Tom Rini <trini@konsulko.com>

arch/sh/cpu/sh4/cache.c

@@ -6,6 +6,7 @@
 
 #include <command.h>
 #include <cpu_func.h>
+#include <stdio.h>
 #include <asm/cache.h>
 #include <asm/io.h>
 #include <asm/processor.h>
@@ -100,6 +101,11 @@ void icache_disable(void)
 	cache_control(CACHE_DISABLE);
 }
 
+void invalidate_icache_all(void)
+{
+	puts("No arch specific invalidate_icache_all available!\n");
+}
+
 int icache_status(void)
 {
 	return 0;