util: Extract flush_icache_range to cacheflush.c

This has been a tcg-specific function, but is also in use
by hardware accelerators via physmem.c.  This can cause
link errors when tcg is disabled.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Joelle van Dyne <j@getutm.app>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214140314.18544-3-richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/tcg/tcg.c b/tcg/tcg.c
index 43c6cf8..ebb9466 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -35,6 +35,7 @@
 #include "qemu/host-utils.h"
 #include "qemu/qemu-print.h"
 #include "qemu/timer.h"
+#include "qemu/cacheflush.h"
 
 /* Note: the long term plan is to reduce the dependencies on the QEMU
    CPU definitions. Currently they are used for qemu_ld/st