alpha: Remove ELF_MACHINE from cpu.h

ELF_MACHINE is unused by target alpha.

Cc: Richard Henderson <rth@twiddle.net>
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Acked-By: NRiku Voipio <riku.voipio@linaro.org>
Signed-off-by: NPeter Crosthwaite <crosthwaite.peter@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

target-alpha/cpu.h

@@ -32,8 +32,6 @@
 
 #include "fpu/softfloat.h"
 
-#define ELF_MACHINE     EM_ALPHA
-
 #define ICACHE_LINE_SIZE 32
 #define DCACHE_LINE_SIZE 32